diff --git a/core/abstractbytearraymodel.h b/core/abstractbytearraymodel.h
--- a/core/abstractbytearraymodel.h
+++ b/core/abstractbytearraymodel.h
@@ -144,7 +144,7 @@
      * @param insertLength number of bytes to copy
      * @return length of inserted data
      */
-    virtual Size insert(Address offset, const Byte* insertData, int insertLength);
+    virtual Size insert(Address offset, const Byte* insertData, Size insertLength);
     Size insert(Address offset, const QByteArray& insertData);
 
     /** removes beginning with position as much as possible
@@ -161,7 +161,7 @@
      * @param insertLength
      * @return length of inserted data
      */
-    virtual Size replace(const AddressRange& removeRange, const Byte* insertData, int insertLength) = 0;
+    virtual Size replace(const AddressRange& removeRange, const Byte* insertData, Size insertLength) = 0;
     /** convenience function, behaves as above */
     Size replace(const AddressRange& removeRange, const QByteArray& insertData);
     /** convenience function, behaves as above */
@@ -223,7 +223,7 @@
      * @param fromOffset the position to start the search
      * @return index of the first  or -1
      */
-    virtual Address indexOf(const Byte* pattern, int patternLength, Address fromOffset = 0, Address toOffset = -1) const;
+    virtual Address indexOf(const Byte* pattern, Size patternLength, Address fromOffset = 0, Address toOffset = -1) const;
     Address indexOf(const QByteArray& pattern, Address fromOffset = 0, Address toOffset = -1) const;
     Address indexOfCaseInsensitive(const CharCodec* charCodec, const QByteArray& pattern, Address fromOffset = 0, Address toOffset = -1) const;
 
@@ -242,7 +242,7 @@
      * @param fromOffset the position to start the search. If -1 the search starts at the end.
      * @return index of the first  or -1
      */
-    virtual Address lastIndexOf(const Byte* pattern, int patternLength, Address fromOffset = -1, Address toOffset = 0) const;
+    virtual Address lastIndexOf(const Byte* pattern, Size patternLength, Address fromOffset = -1, Address toOffset = 0) const;
     Address lastIndexOf(const QByteArray& pattern, Address fromOffset = -1, Address toOffset = 0) const;
     Address lastIndexOfCaseInsensitive(const CharCodec* charCodec, const QByteArray& pattern, Address fromOffset = -1, Address toOffset = 0) const;
 
diff --git a/core/abstractbytearraymodel.cpp b/core/abstractbytearraymodel.cpp
--- a/core/abstractbytearraymodel.cpp
+++ b/core/abstractbytearraymodel.cpp
@@ -43,7 +43,7 @@
     Q_UNUSED(isReadOnly)
 }
 
-Size AbstractByteArrayModel::insert(Address offset, const Byte* insertData, int insertLength)
+Size AbstractByteArrayModel::insert(Address offset, const Byte* insertData, Size insertLength)
 {
     return replace(offset, 0, insertData, insertLength);
 }
@@ -67,7 +67,7 @@
     return copyRange.width();
 }
 
-Address AbstractByteArrayModel::indexOf(const Byte* pattern, int patternLength, Address fromOffset, Address toOffset) const
+Address AbstractByteArrayModel::indexOf(const Byte* pattern, Size patternLength, Address fromOffset, Address toOffset) const
 {
     Address result = -1;
 
@@ -76,7 +76,7 @@
     Size nextSignalByteCount = fromOffset + SearchedByteCountSignalLimit;
 
     for (Address i = fromOffset; i <= lastFrom; ++i) {
-        int c = 0;
+	Size c = 0;
         for (; c < patternLength; ++c) {
             if (pattern[c] != byte(i + c)) {
                 break;
@@ -97,7 +97,7 @@
     return result;
 }
 
-Address AbstractByteArrayModel::lastIndexOf(const Byte* pattern, int patternLength, Address fromOffset, Address toOffset) const
+Address AbstractByteArrayModel::lastIndexOf(const Byte* pattern, Size patternLength, Address fromOffset, Address toOffset) const
 {
     Address result = -1;
 
@@ -116,7 +116,7 @@
     Size nextSignalByteCount = fromOffset - SearchedByteCountSignalLimit;
 
     for (Address i = fromOffset; i >= toOffset; --i) {
-        int c = 0;
+	Size c = 0;
         for (; c < patternLength; ++c) {
             if (pattern[c] != byte(i + c)) {
                 break;
diff --git a/core/address.h b/core/address.h
--- a/core/address.h
+++ b/core/address.h
@@ -28,8 +28,7 @@
 
 namespace Okteta {
 
-// Address needs to be <= int, as long as we use QByteArray and its int parameters
-using Address = qint32;
+using Address = qint64;
 
 }
 
diff --git a/core/arraychangemetrics.h b/core/arraychangemetrics.h
--- a/core/arraychangemetrics.h
+++ b/core/arraychangemetrics.h
@@ -59,7 +59,7 @@
 
 public:
     ArrayChangeMetrics();
-    ArrayChangeMetrics(Type type, Address offset, qint32 secondArgument, qint32 thirdArgument);
+    ArrayChangeMetrics(Type type, Address offset, qint64 secondArgument, qint64 thirdArgument);
 
 public:
     bool operator==(const ArrayChangeMetrics& other) const;
@@ -89,13 +89,13 @@
     // TODO: how to make the arguments of the size of the largest union member?
     union
     {
-        qint32 mSecondArgument = 0;
+	qint64 mSecondArgument = 0;
         Size mRemoveLength;
         Address mSecondStart;
     };
     union
     {
-        qint32 mThirdArgument = 0;
+	qint64 mThirdArgument = 0;
         Size mInsertLength;
         Size mSecondLength;
     };
@@ -112,7 +112,7 @@
     return {Swapping, firstOffset, secondOffset, secondLength};
 }
 
-inline ArrayChangeMetrics::ArrayChangeMetrics(Type type, Address offset, qint32 secondArgument, qint32 thirdArgument)
+inline ArrayChangeMetrics::ArrayChangeMetrics(Type type, Address offset, qint64 secondArgument, qint64 thirdArgument)
     : mType(type)
     , mOffset(offset)
     , mSecondArgument(secondArgument)
diff --git a/core/bookmarkable.h b/core/bookmarkable.h
--- a/core/bookmarkable.h
+++ b/core/bookmarkable.h
@@ -23,6 +23,8 @@
 #ifndef OKTETA_BOOKMARKABLE_H
 #define OKTETA_BOOKMARKABLE_H
 
+#include <okteta/address.h>
+#include <okteta/size.h>
 // Qt
 #include <QtPlugin>
 
@@ -49,8 +51,8 @@
     virtual Okteta::BookmarksConstIterator createBookmarksConstIterator() const = 0;
 //     virtual BookmarksMutableIterator createBookmarksMutableIterator() const = 0;
     virtual const Okteta::Bookmark& bookmarkAt(unsigned int index) const = 0;
-    virtual const Okteta::Bookmark& bookmarkFor(int offset) const = 0;
-    virtual bool containsBookmarkFor(int offset) const = 0;
+    virtual const Okteta::Bookmark& bookmarkFor(Okteta::Address offset) const = 0;
+    virtual bool containsBookmarkFor(Okteta::Address offset) const = 0;
     virtual unsigned int bookmarksCount() const = 0;
 
 public: // signal
diff --git a/core/bytearraymodel.h b/core/bytearraymodel.h
--- a/core/bytearraymodel.h
+++ b/core/bytearraymodel.h
@@ -59,9 +59,9 @@
     bool isReadOnly() const override;
     bool isModified() const override;
 
-    Size insert(Address offset, const Byte* insertData, int insertLength) override;
+    Size insert(Address offset, const Byte* insertData, Size insertLength) override;
     Size remove(const AddressRange& removeRange) override;
-    Size replace(const AddressRange& removeRange, const Byte* insertData, int insertLength) override;
+    Size replace(const AddressRange& removeRange, const Byte* insertData, Size insertLength) override;
     bool swap(Address firstStart, const AddressRange& secondRange) override;
     Size fill(Byte fillByte, Address offset = 0, Size fillLength = -1) override;
     void setByte(Address offset, Byte byte) override;
@@ -77,8 +77,8 @@
 
     Okteta::BookmarksConstIterator createBookmarksConstIterator() const override;
     const Okteta::Bookmark& bookmarkAt(unsigned int index) const override;
-    const Okteta::Bookmark& bookmarkFor(int offset) const override;
-    bool containsBookmarkFor(int offset) const override;
+    const Okteta::Bookmark& bookmarkFor(Okteta::Address offset) const override;
+    bool containsBookmarkFor(Okteta::Address offset) const override;
     unsigned int bookmarksCount() const override;
 
 Q_SIGNALS: // Okteta::Bookmarkable API
diff --git a/core/bytearraymodel.cpp b/core/bytearraymodel.cpp
--- a/core/bytearraymodel.cpp
+++ b/core/bytearraymodel.cpp
@@ -81,7 +81,7 @@
     d->setByte(offset, byte);
 }
 
-Size ByteArrayModel::insert(Address offset, const Byte* insertData, int insertLength)
+Size ByteArrayModel::insert(Address offset, const Byte* insertData, Size insertLength)
 {
     return d->insert(offset, insertData, insertLength);
 }
@@ -91,7 +91,7 @@
     return d->remove(removeRange);
 }
 
-Size ByteArrayModel::replace(const AddressRange& removeRange, const Byte* insertData, int insertLength)
+Size ByteArrayModel::replace(const AddressRange& removeRange, const Byte* insertData, Size insertLength)
 {
     return d->replace(removeRange, insertData, insertLength);
 }
@@ -131,7 +131,7 @@
     return d->createBookmarksConstIterator();
 }
 
-const Okteta::Bookmark& ByteArrayModel::bookmarkFor(int offset) const
+const Okteta::Bookmark& ByteArrayModel::bookmarkFor(Address offset) const
 {
     return d->bookmarkFor(offset);
 }
@@ -141,7 +141,7 @@
     return d->bookmarkAt(index);
 }
 
-bool ByteArrayModel::containsBookmarkFor(int offset) const
+bool ByteArrayModel::containsBookmarkFor(Address offset) const
 {
     return d->containsBookmarkFor(offset);
 }
diff --git a/core/changesdatastorage.h b/core/changesdatastorage.h
--- a/core/changesdatastorage.h
+++ b/core/changesdatastorage.h
@@ -23,6 +23,8 @@
 #ifndef OKTETA_CHANGESDATASTORAGE_H
 #define OKTETA_CHANGESDATASTORAGE_H
 
+#include <okteta/address.h>
+#include <okteta/size.h>
 // Qt
 #include <QByteArray>
 
@@ -34,15 +36,15 @@
     ChangesDataStorage();
 
 public: // set/action
-    void append(int from, char byte);
-    void append(int from, const char* data, int dataLength);
-    void appendFill(int from, char fillDatum, int fillLength);
+    void append(Address from, char byte);
+    void append(Address from, const char* data, Size dataLength);
+    void appendFill(Address from, char fillDatum, Size fillLength);
 
     void clear();
 
 public: // get
-    QByteArray data(int offset, int length) const;
-    char operator[](int offset) const;
+    QByteArray data(Address offset, Size length) const;
+    char operator[](Address offset) const;
 
 protected:
     QByteArray mData;
@@ -50,28 +52,28 @@
 
 inline ChangesDataStorage::ChangesDataStorage() = default;
 
-inline QByteArray ChangesDataStorage::data(int offset, int length) const
+inline QByteArray ChangesDataStorage::data(Address offset, Size length) const
 {
     return mData.mid(offset, length);
 }
 
-inline char ChangesDataStorage::operator[](int offset) const { return mData[offset]; }
+inline char ChangesDataStorage::operator[](Address offset) const { return mData[(int)offset]; }
 
 inline void ChangesDataStorage::clear() { mData.clear(); }
 
-inline void ChangesDataStorage::append(int from, char datum)
+inline void ChangesDataStorage::append(Address from, char datum)
 {
     mData.resize(from);
     mData.append(datum);
 }
 
-inline void ChangesDataStorage::append(int from, const char* data, int dataLength)
+inline void ChangesDataStorage::append(Address from, const char* data, Size dataLength)
 {
     mData.resize(from + dataLength);
     memcpy(mData.data() + from, data, dataLength);
 }
 
-inline void ChangesDataStorage::appendFill(int from, char fillDatum, int fillLength)
+inline void ChangesDataStorage::appendFill(Address from, char fillDatum, Size fillLength)
 {
     mData.resize(from + fillLength);
     memset(mData.data() + from, fillDatum, fillLength);
diff --git a/core/filebytearraymodel.h b/core/filebytearraymodel.h
--- a/core/filebytearraymodel.h
+++ b/core/filebytearraymodel.h
@@ -51,9 +51,9 @@
     bool isReadOnly() const override;
     bool isModified() const override;
 
-    Size insert(Address offset, const Byte* insertData, int insertLength) override;
+    Size insert(Address offset, const Byte* insertData, Size insertLength) override;
     Size remove(const AddressRange& removeRange) override;
-    Size replace(const AddressRange& removeRange, const Byte* insertData, int insertLength) override;
+    Size replace(const AddressRange& removeRange, const Byte* insertData, Size insertLength) override;
     bool swap(Address firstStart, const AddressRange& secondRange) override;
     Size fill(Byte fillByte, Address offset = 0, Size fillLength = -1) override;
     void setByte(Address offset, Byte byte) override;
diff --git a/core/filebytearraymodel.cpp b/core/filebytearraymodel.cpp
--- a/core/filebytearraymodel.cpp
+++ b/core/filebytearraymodel.cpp
@@ -50,9 +50,9 @@
 void FileByteArrayModel::setByte(Address, Byte)  {}
 Byte FileByteArrayModel::byte(Address offset) const { return d->byte(offset); }
 
-Size FileByteArrayModel::insert(Address /*Pos*/, const Byte*, int /*Length*/) {  return 0; }
+Size FileByteArrayModel::insert(Address /*Pos*/, const Byte*, Size /*Length*/) {  return 0; }
 Size FileByteArrayModel::remove(const AddressRange& /*Section*/) {  return 0; }
-Size FileByteArrayModel::replace(const AddressRange& /*Section*/, const Byte*, int /*Length*/) {  return 0; }
+Size FileByteArrayModel::replace(const AddressRange& /*Section*/, const Byte*, Size /*Length*/) {  return 0; }
 Size FileByteArrayModel::fill(Byte /*FillChar*/, Address /*Pos*/, Size /*Length*/) {  return 0; }
 bool FileByteArrayModel::swap(Address /*DestPos*/, const AddressRange& /*SourceSection*/) { return false; }
 
diff --git a/core/filebytearraymodel_p.h b/core/filebytearraymodel_p.h
--- a/core/filebytearraymodel_p.h
+++ b/core/filebytearraymodel_p.h
@@ -76,7 +76,7 @@
     /** */
     mutable KPageOfChar mData;
     /** */
-    int mSize = 0;
+    Size mSize = 0;
 
     /** current offset */
     mutable unsigned int mOffsetOfActualPage;
diff --git a/core/filebytearraymodel_p.cpp b/core/filebytearraymodel_p.cpp
--- a/core/filebytearraymodel_p.cpp
+++ b/core/filebytearraymodel_p.cpp
@@ -73,7 +73,7 @@
         return false;
     }
 
-    int fileSize = mFile.size();
+    const qint64 fileSize = mFile.size();
     mSize = fileSize;
 
     // calculate necessary number of pages
diff --git a/core/fixedsizebytearraymodel.h b/core/fixedsizebytearraymodel.h
--- a/core/fixedsizebytearraymodel.h
+++ b/core/fixedsizebytearraymodel.h
@@ -40,9 +40,9 @@
 
 public:
     /** creates a readonly buffer around the given data */
-    FixedSizeByteArrayModel(Byte* data, int size, Byte fillUpChar = '\0', QObject* parent = nullptr);
+    FixedSizeByteArrayModel(Byte* data, Size size, Byte fillUpChar = '\0', QObject* parent = nullptr);
     /** creates a writeable buffer which is deleted at the end */
-    explicit FixedSizeByteArrayModel(int size, Byte fillUpChar = '\0', QObject* parent = nullptr);
+    explicit FixedSizeByteArrayModel(Size size, Byte fillUpChar = '\0', QObject* parent = nullptr);
 
     ~FixedSizeByteArrayModel() override;
 
@@ -52,9 +52,9 @@
     bool isReadOnly() const override;
     bool isModified() const override;
 
-    Size insert(Address offset, const Byte* insertData, int insertLength) override;
+    Size insert(Address offset, const Byte* insertData, Size insertLength) override;
     Size remove(const AddressRange& removeRange) override;
-    Size replace(const AddressRange& removeRange, const Byte* insertData, int insertLength) override;
+    Size replace(const AddressRange& removeRange, const Byte* insertData, Size insertLength) override;
     bool swap(Address firstStart, const AddressRange& secondRange) override;
     Size fill(Byte fillByte, Address offset = 0, Size fillLength = -1) override;
     void setByte(Address offset, Byte byte) override;
@@ -71,13 +71,13 @@
     Byte* rawData() const;
 
 protected:
-    void reset(unsigned int pos, unsigned int length);
+    void reset(Address pos, Size length);
 
 protected:
     /** */
     Byte* mData;
     /***/
-    int mSize;
+    Size mSize;
     /** */
     Byte mFillUpByte;
     /**  */
diff --git a/core/fixedsizebytearraymodel.cpp b/core/fixedsizebytearraymodel.cpp
--- a/core/fixedsizebytearraymodel.cpp
+++ b/core/fixedsizebytearraymodel.cpp
@@ -29,7 +29,7 @@
 
 namespace Okteta {
 
-FixedSizeByteArrayModel::FixedSizeByteArrayModel(Byte* data, int size, Byte fillUpByte, QObject* parent)
+FixedSizeByteArrayModel::FixedSizeByteArrayModel(Byte* data, Size size, Byte fillUpByte, QObject* parent)
     : AbstractByteArrayModel(parent)
     , mData(data)
     , mSize(size)
@@ -40,7 +40,7 @@
 {
 }
 
-FixedSizeByteArrayModel::FixedSizeByteArrayModel(int size, Byte fillUpByte, QObject* parent)
+FixedSizeByteArrayModel::FixedSizeByteArrayModel(Size size, Byte fillUpByte, QObject* parent)
     : AbstractByteArrayModel(parent)
     , mData(new Byte[size])
     , mSize(size)
@@ -72,7 +72,7 @@
     }
 }
 
-Size FixedSizeByteArrayModel::insert(Address offset, const Byte* insertData, int insertLength)
+Size FixedSizeByteArrayModel::insert(Address offset, const Byte* insertData, Size insertLength)
 {
     // check all parameters
     if (offset >= mSize || insertLength == 0) {
@@ -131,7 +131,7 @@
     return removeLength;
 }
 
-Size FixedSizeByteArrayModel::replace(const AddressRange& _removeRange, const Byte* insertData, int insertLength)
+Size FixedSizeByteArrayModel::replace(const AddressRange& _removeRange, const Byte* insertData, Size insertLength)
 {
     AddressRange removeRange(_removeRange);
     // check all parameters
@@ -329,7 +329,7 @@
     return valueByLength;
 }
 
-void FixedSizeByteArrayModel::reset(unsigned int offset, unsigned int length)
+void FixedSizeByteArrayModel::reset(Address offset, Size length)
 {
     memset(&mData[offset], mFillUpByte, length);
 }
diff --git a/core/piecetable/tests/revertablepiecetabletest.cpp b/core/piecetable/tests/revertablepiecetabletest.cpp
--- a/core/piecetable/tests/revertablepiecetabletest.cpp
+++ b/core/piecetable/tests/revertablepiecetabletest.cpp
@@ -54,7 +54,7 @@
 
     pieceTable.init(BaseSize);
     int storageId;
-    int storageOffset;
+    Address storageOffset;
 
     QCOMPARE(pieceTable.size(), BaseSize);
     QCOMPARE(pieceTable.changesCount(), 0);
@@ -86,7 +86,7 @@
 
 static void fillWithSize(RevertablePieceTable* pieceTable, int count)
 {
-    int dummy;
+    Size dummy;
     pieceTable->init(0);
     for (int i = 0; i < count; ++i) {
         pieceTable->insert(0, BaseSize, &dummy);
@@ -98,7 +98,7 @@
     RevertablePieceTable pieceTable;
 
     int storageId;
-    int storageOffset;
+    Address storageOffset;
     bool result;
 
     // inserting to empty
@@ -465,7 +465,7 @@
 
     int changeStarts[6];
     int storageId;
-    int storageOffset;
+    Address storageOffset;
     bool result;
 
     // removing at begin
@@ -862,7 +862,7 @@
     RevertablePieceTable pieceTable;
 
     int storageId;
-    int storageOffset;
+    Address storageOffset;
     bool result;
 
     // moving end at begin
diff --git a/core/piecetable/tests/testpiecetablechange.h b/core/piecetable/tests/testpiecetablechange.h
--- a/core/piecetable/tests/testpiecetablechange.h
+++ b/core/piecetable/tests/testpiecetablechange.h
@@ -35,8 +35,8 @@
 {
 public:
     TestPieceTableChange(int typeId = -1, const QString& description = QString(),
-                         int position = 0, int storagePosition = 0, int storageId = Piece::ChangeStorage,
-                         int replacedStoragePosition = 0, int replacedStorageId = Piece::ChangeStorage);
+			 Address position = 0, Address storagePosition = 0, int storageId = Piece::ChangeStorage,
+			 Address replacedStoragePosition = 0, int replacedStorageId = Piece::ChangeStorage);
 
     ~TestPieceTableChange() override;
 
@@ -47,22 +47,22 @@
     AddressRange apply(PieceTable* pieceTable) const override;
     AddressRange revert(PieceTable* pieceTable) const override;
     ArrayChangeMetrics metrics() const override;
-    int dataSize() const override;
+    Size dataSize() const override;
 
 protected:
     int mTypeId;
     QString mDescription;
-    int mPosition;
-    int mStoragePosition;
+    Address mPosition;
+    Address mStoragePosition;
     int mStorageId;
 
-    int mReplacedStoragePosition;
+    Address mReplacedStoragePosition;
     int mReplacedStorageId;
 };
 
 inline TestPieceTableChange::TestPieceTableChange(int typeId, const QString& description,
-                                                  int position, int storagePosition, int storageId,
-                                                  int replacedStoragePosition, int replacedStorageId)
+						  Address position, Address storagePosition, int storageId,
+						  Address replacedStoragePosition, int replacedStorageId)
     : mTypeId(typeId)
     , mDescription(description)
     , mPosition(position)
diff --git a/core/piecetable/tests/testpiecetablechange.cpp b/core/piecetable/tests/testpiecetablechange.cpp
--- a/core/piecetable/tests/testpiecetablechange.cpp
+++ b/core/piecetable/tests/testpiecetablechange.cpp
@@ -70,6 +70,6 @@
     return ArrayChangeMetrics::asReplacement(mPosition, 1, 1);
 }
 
-int TestPieceTableChange::dataSize() const { return 1; }
+Size TestPieceTableChange::dataSize() const { return 1; }
 
 }
diff --git a/core/piecetablebytearraymodel.h b/core/piecetablebytearraymodel.h
--- a/core/piecetablebytearraymodel.h
+++ b/core/piecetablebytearraymodel.h
@@ -66,9 +66,9 @@
     bool isReadOnly() const override;
     bool isModified() const override;
 
-    Size insert(Address offset, const Byte* insertData, int insertLength) override;
+    Size insert(Address offset, const Byte* insertData, Size insertLength) override;
     Size remove(const AddressRange& removeRange) override;
-    Size replace(const AddressRange& removeRange, const Byte* insertData, int insertLength) override;
+    Size replace(const AddressRange& removeRange, const Byte* insertData, Size insertLength) override;
     bool swap(Address firstStart, const AddressRange& secondRange) override;
     Size fill(Byte fillByte, Address offset = 0, Size fillLength = -1) override;
     void setByte(Address offset, Byte byte) override;
@@ -95,8 +95,8 @@
 
     Okteta::BookmarksConstIterator createBookmarksConstIterator() const override;
     const Okteta::Bookmark& bookmarkAt(unsigned int index) const override;
-    const Okteta::Bookmark& bookmarkFor(int offset) const override;
-    bool containsBookmarkFor(int offset) const override;
+    const Okteta::Bookmark& bookmarkFor(Address offset) const override;
+    bool containsBookmarkFor(Address offset) const override;
     unsigned int bookmarksCount() const override;
 
 public: // ChangesDescribable API
diff --git a/core/piecetablebytearraymodel.cpp b/core/piecetablebytearraymodel.cpp
--- a/core/piecetablebytearraymodel.cpp
+++ b/core/piecetablebytearraymodel.cpp
@@ -60,7 +60,7 @@
     d->setByte(offset, byte);
 }
 
-Size PieceTableByteArrayModel::insert(Address offset, const Byte* insertData, int insertLength)
+Size PieceTableByteArrayModel::insert(Address offset, const Byte* insertData, Size insertLength)
 {
     return d->insert(offset, insertData, insertLength);
 }
@@ -70,7 +70,7 @@
     return d->remove(removeRange);
 }
 
-Size PieceTableByteArrayModel::replace(const AddressRange& removeRange, const Byte* insertData, int insertLength)
+Size PieceTableByteArrayModel::replace(const AddressRange& removeRange, const Byte* insertData, Size insertLength)
 {
     return d->replace(removeRange, insertData, insertLength);
 }
@@ -132,12 +132,12 @@
     return d->bookmarkAt(index);
 }
 
-const Okteta::Bookmark& PieceTableByteArrayModel::bookmarkFor(int offset) const
+const Okteta::Bookmark& PieceTableByteArrayModel::bookmarkFor(Address offset) const
 {
     return d->bookmarkFor(offset);
 }
 
-bool PieceTableByteArrayModel::containsBookmarkFor(int offset) const
+bool PieceTableByteArrayModel::containsBookmarkFor(Address offset) const
 {
     return d->containsBookmarkFor(offset);
 }
diff --git a/core/piecetablebytearraymodel_p.h b/core/piecetablebytearraymodel_p.h
--- a/core/piecetablebytearraymodel_p.h
+++ b/core/piecetablebytearraymodel_p.h
@@ -41,7 +41,7 @@
     /**  */
     explicit PieceTableByteArrayModelPrivate(PieceTableByteArrayModel* parent, const QByteArray& data);
     /** creates a writeable buffer which is deleted at the end */
-    explicit PieceTableByteArrayModelPrivate(PieceTableByteArrayModel* parent, int size, Byte fillByte = '\0');
+    explicit PieceTableByteArrayModelPrivate(PieceTableByteArrayModel* parent, Size size, Byte fillByte = '\0');
     PieceTableByteArrayModelPrivate() = delete;
 
     ~PieceTableByteArrayModelPrivate();
@@ -52,9 +52,9 @@
     bool isReadOnly() const;
     bool isModified() const;
 
-    Size insert(Address offset, const Byte* insertData, int insertLength);
+    Size insert(Address offset, const Byte* insertData, Size insertLength);
     Size remove(const AddressRange& removeRange);
-    Size replace(const AddressRange& removeRange, const Byte* insertData, int insertLength);
+    Size replace(const AddressRange& removeRange, const Byte* insertData, Size insertLength);
     bool swap(Address firstStart, const AddressRange& secondRange);
     Size fill(Byte fillByte, Address offset = 0, Size fillLength = -1);
     void setByte(Address offset, Byte byte);
@@ -78,8 +78,8 @@
 
     BookmarksConstIterator createBookmarksConstIterator() const;
     const Bookmark& bookmarkAt(unsigned int index) const;
-    const Bookmark& bookmarkFor(int offset) const;
-    bool containsBookmarkFor(int offset) const;
+    const Bookmark& bookmarkFor(Address offset) const;
+    bool containsBookmarkFor(Address offset) const;
     unsigned int bookmarksCount() const;
 
 public: // ChangesDescribable API
@@ -97,12 +97,12 @@
     void setData(const QByteArray& data);
 
 protected:
-    void doInsertChange(Address offset, const Byte* insertData, int insertLength);
+    void doInsertChange(Address offset, const Byte* insertData, Size insertLength);
     void doRemoveChange(const AddressRange& removeRange);
-    void doReplaceChange(const AddressRange& removeRange, const Byte* insertData, int insertLength);
+    void doReplaceChange(const AddressRange& removeRange, const Byte* insertData, Size insertLength);
     void doSwapChange(Address firstStart, const AddressRange& secondRange);
     void doFillChange(Address offset, Size filledLength,
-                      Byte fillByte, int fillLength);
+		      Byte fillByte, Size fillLength);
 
     void beginChanges();
     void endChanges();
@@ -190,11 +190,11 @@
 {
     return mBookmarks.at(index);
 }
-inline const Bookmark& PieceTableByteArrayModelPrivate::bookmarkFor(int offset) const
+inline const Bookmark& PieceTableByteArrayModelPrivate::bookmarkFor(Address offset) const
 {
     return mBookmarks.bookmark(offset);
 }
-inline bool PieceTableByteArrayModelPrivate::containsBookmarkFor(int offset) const { return mBookmarks.contains(offset); }
+inline bool PieceTableByteArrayModelPrivate::containsBookmarkFor(Address offset) const { return mBookmarks.contains(offset); }
 inline unsigned int PieceTableByteArrayModelPrivate::bookmarksCount() const { return mBookmarks.size(); }
 
 }
diff --git a/core/piecetablebytearraymodel_p.cpp b/core/piecetablebytearraymodel_p.cpp
--- a/core/piecetablebytearraymodel_p.cpp
+++ b/core/piecetablebytearraymodel_p.cpp
@@ -38,7 +38,7 @@
     mPieceTable.init(data.size());
 }
 
-PieceTableByteArrayModelPrivate::PieceTableByteArrayModelPrivate(PieceTableByteArrayModel* parent, int size, Byte fillByte)
+PieceTableByteArrayModelPrivate::PieceTableByteArrayModelPrivate(PieceTableByteArrayModel* parent, Size size, Byte fillByte)
     : p(parent)
     , mReadOnly(false)
     , mInitialData(size, fillByte)
@@ -56,14 +56,14 @@
     mPieceTable.getStorageData(&storageId, &storageOffset, offset);
 
     const Byte result = (storageId == KPieceTable::Piece::OriginalStorage) ?
-                        mInitialData[storageOffset] :
+                        mInitialData[(int)storageOffset] :
                         mChangesDataStorage[storageOffset];
     return result;
 }
 
 void PieceTableByteArrayModelPrivate::setData(const QByteArray& data)
 {
-    const int oldSize = mPieceTable.size();
+    const Size oldSize = mPieceTable.size();
     const bool wasModifiedBefore = isModified();
     const QList<Bookmark> bookmarks = mBookmarks.list();
 
@@ -115,10 +115,10 @@
     }
 }
 
-Size PieceTableByteArrayModelPrivate::insert(Address offset, const Byte* insertData, int insertLength)
+Size PieceTableByteArrayModelPrivate::insert(Address offset, const Byte* insertData, Size insertLength)
 {
     // correct parameters
-    const int oldSize = mPieceTable.size();
+    const Size oldSize = mPieceTable.size();
     if (offset > oldSize) {
         offset = oldSize;
     }
@@ -141,7 +141,7 @@
 {
     AddressRange removeRange(_removeRange);
     // correct parameters
-    const int oldSize = mPieceTable.size();
+    const Size oldSize = mPieceTable.size();
     removeRange.restrictEndTo(oldSize - 1);
     // check parameters
     if (removeRange.start() >= oldSize || removeRange.width() == 0) {
@@ -157,11 +157,11 @@
     return removeRange.width();
 }
 
-Size PieceTableByteArrayModelPrivate::replace(const AddressRange& _removeRange, const Byte* insertData, int insertLength)
+Size PieceTableByteArrayModelPrivate::replace(const AddressRange& _removeRange, const Byte* insertData, Size insertLength)
 {
     AddressRange removeRange(_removeRange);
     // correct parameters
-    const int oldSize = mPieceTable.size();
+    const Size oldSize = mPieceTable.size();
     removeRange.restrictEndTo(oldSize - 1);
     // check parameters
     if ((removeRange.startsBehind(oldSize - 1) && removeRange.width() > 0)
@@ -201,13 +201,13 @@
 Size PieceTableByteArrayModelPrivate::fill(Byte fillByte, Address offset, Size fillLength)
 {
     // correct parameters
-    const int lengthToEnd = mPieceTable.size() - offset;
+    const Size lengthToEnd = mPieceTable.size() - offset;
     if (fillLength < 0) {
         fillLength = lengthToEnd;
     }
-    const int filledLength = (fillLength < lengthToEnd) ? fillLength : lengthToEnd;
+    const Size filledLength = (fillLength < lengthToEnd) ? fillLength : lengthToEnd;
     // check parameters
-    const bool nothingToFill = (((int)offset >= mPieceTable.size()) || (fillLength == 0));
+    const bool nothingToFill = (((Size)offset >= mPieceTable.size()) || (fillLength == 0));
     if (nothingToFill) {
         return 0;
     }
@@ -317,7 +317,7 @@
         {
         case ArrayChangeMetrics::Replacement:
         {
-            const int oldSize = mPieceTable.size();
+        const Size oldSize = mPieceTable.size();
             const AddressRange removeRange = AddressRange::fromWidth(metrics.offset(), metrics.removeLength());
             // check parameters
             if (removeRange.startsBehind(oldSize - 1) && (removeRange.width() > 0)) {
@@ -382,7 +382,7 @@
 }
 
 void PieceTableByteArrayModelPrivate::doInsertChange(Address offset,
-                                                     const Byte* insertData, int insertLength)
+                             const Byte* insertData, Size insertLength)
 {
     Address storageOffset;
     mPieceTable.insert(offset, insertLength, &storageOffset);
@@ -412,7 +412,7 @@
 }
 
 void PieceTableByteArrayModelPrivate::doReplaceChange(const AddressRange& removeRange,
-                                                      const Byte* insertData, int insertLength)
+                              const Byte* insertData, Size insertLength)
 {
     Address storageOffset;
     mPieceTable.replace(removeRange, insertLength, &storageOffset);
@@ -443,7 +443,7 @@
 }
 
 void PieceTableByteArrayModelPrivate::doFillChange(Address offset, Size filledLength,
-                                                   Byte fillByte, int fillLength)
+                           Byte fillByte, Size fillLength)
 {
     Address storageOffset;
     mPieceTable.replace(offset, filledLength, fillLength, &storageOffset);
diff --git a/core/size.h b/core/size.h
--- a/core/size.h
+++ b/core/size.h
@@ -28,7 +28,7 @@
 
 namespace Okteta {
 
-using Size = qint32;
+using Size = qint64;
 
 }
 
diff --git a/gui/abstractbytearraycolumnrenderer.h b/gui/abstractbytearraycolumnrenderer.h
--- a/gui/abstractbytearraycolumnrenderer.h
+++ b/gui/abstractbytearraycolumnrenderer.h
@@ -79,7 +79,7 @@
 
 public:
     // void renderLine( QPainter* painter, int lineIndex );
-    void renderLinePositions(QPainter* painter, Line lineIndex, const LineRange& linePositions);
+    void renderLinePositions(QPainter* painter, Line lineIndex, const LinePositionRange& linePositions);
     /** paints a cursor based on the type of the byte.
      * @param byteIndex Index of the byte to paint the cursor for. If -1 a space is used as char.
      */
diff --git a/gui/abstractbytearrayview.h b/gui/abstractbytearrayview.h
--- a/gui/abstractbytearrayview.h
+++ b/gui/abstractbytearrayview.h
@@ -461,7 +461,7 @@
     bool viewportEvent(QEvent* event) override;
 
 protected: // ColumnsView API
-    void setNoOfLines(int newNoOfLines) override;
+    void setNoOfLines(LineSize newNoOfLines) override;
 
 protected: // Q_SLOTS QWidget API
     void changeEvent(QEvent* event) override;
diff --git a/gui/abstractbytearrayview.cpp b/gui/abstractbytearrayview.cpp
--- a/gui/abstractbytearrayview.cpp
+++ b/gui/abstractbytearrayview.cpp
@@ -455,7 +455,7 @@
     d->setZoomLevel(zoomLevel);
 }
 
-void AbstractByteArrayView::setNoOfLines(int newNoOfLines)
+void AbstractByteArrayView::setNoOfLines(LineSize newNoOfLines)
 {
     ColumnsView::setNoOfLines(newNoOfLines > 1 ? newNoOfLines : 1);
 }
diff --git a/gui/abstractbytearrayview_p.cpp b/gui/abstractbytearrayview_p.cpp
--- a/gui/abstractbytearrayview_p.cpp
+++ b/gui/abstractbytearrayview_p.cpp
@@ -82,7 +82,7 @@
     bool isModified() const override;
 
 public: // modification API
-    Size replace(const AddressRange& removeSection, const Byte* insertData, int insertLength) override;
+    Size replace(const AddressRange& removeSection, const Byte* insertData, Size insertLength) override;
     bool swap(Address firstStart, const AddressRange& secondRange) override;
     Size fill(Byte fillByte, Address offset = 0, Size fillLength = -1) override;
     void setByte(Address offset, Byte byte) override;
@@ -95,7 +95,7 @@
 Byte NullModel::byte(Address offset) const { Q_UNUSED(offset) return 0; }
 Size NullModel::size() const { return 0; }
 bool NullModel::isModified() const { return false; }
-Size NullModel::replace(const AddressRange& removeSection, const Byte* insertData, int insertLength)
+Size NullModel::replace(const AddressRange& removeSection, const Byte* insertData, Size insertLength)
 {
     Q_UNUSED(removeSection) Q_UNUSED(insertData) Q_UNUSED(insertLength)
     return 0;
diff --git a/gui/libcolumnsview/abstractcolumnrenderer.h b/gui/libcolumnsview/abstractcolumnrenderer.h
--- a/gui/libcolumnsview/abstractcolumnrenderer.h
+++ b/gui/libcolumnsview/abstractcolumnrenderer.h
@@ -24,6 +24,7 @@
 #define OKTETA_ABSTRACTCOLUMNRENDERER_H
 
 // lib
+#include <okteta/line.h>
 #include <okteta/kadds.h>
 #include <okteta/oktetagui_export.h>
 
@@ -59,7 +60,7 @@
      * @param xSpan
      * @param firstLineIndex no of the first of the range of lines to paint
      */
-    virtual void renderFirstLine(QPainter* painter, const PixelXRange& xSpan, int firstLineIndex);
+    virtual void renderFirstLine(QPainter* painter, const PixelXRange& xSpan, Line firstLineIndex);
     /** the actual painting call for a column's line.
      * The default implementation simply paints the background
      */
diff --git a/gui/libcolumnsview/abstractcolumnrenderer.cpp b/gui/libcolumnsview/abstractcolumnrenderer.cpp
--- a/gui/libcolumnsview/abstractcolumnrenderer.cpp
+++ b/gui/libcolumnsview/abstractcolumnrenderer.cpp
@@ -58,7 +58,7 @@
 
 bool AbstractColumnRenderer::overlaps(const PixelXRange& xSpan) const { return d->mXSpan.overlaps(xSpan); }
 
-void AbstractColumnRenderer::renderFirstLine(QPainter* painter, const PixelXRange& xSpan, int firstLineIndex)
+void AbstractColumnRenderer::renderFirstLine(QPainter* painter, const PixelXRange& xSpan, Line firstLineIndex)
 {
     Q_UNUSED(xSpan)
     Q_UNUSED(firstLineIndex)
diff --git a/gui/line.h b/gui/line.h
--- a/gui/line.h
+++ b/gui/line.h
@@ -28,8 +28,8 @@
 
 namespace Okteta {
 
-using Line = qint32;
-using LineSize = qint32;
+using Line = qint64;
+using LineSize = qint64;
 
 }
 
diff --git a/gui/lineposition.h b/gui/lineposition.h
--- a/gui/lineposition.h
+++ b/gui/lineposition.h
@@ -28,6 +28,7 @@
 
 namespace Okteta {
 
+// Number type for positions within a line
 using LinePosition = qint32;
 using LinePositionSize = qint32;
 
diff --git a/kasten/gui/io/streamencoder/ihex/bytearrayihexstreamencoder.cpp b/kasten/gui/io/streamencoder/ihex/bytearrayihexstreamencoder.cpp
--- a/kasten/gui/io/streamencoder/ihex/bytearrayihexstreamencoder.cpp
+++ b/kasten/gui/io/streamencoder/ihex/bytearrayihexstreamencoder.cpp
@@ -180,8 +180,8 @@
                 }
             }
             nextUpperAddressChangeDataEnd = 0x10000 - (i & 0xFFFF);
-            nextDataEnd = qMin(dataPerLineCount,
-                               qMin(range.end() - i + 1, nextUpperAddressChangeDataEnd));
+            nextDataEnd = (int)qMin((Okteta::Address)dataPerLineCount,
+                                    qMin(range.end() - i + 1, (Okteta::Address)nextUpperAddressChangeDataEnd));
             d = 0;
         }
     }
diff --git a/kasten/gui/io/streamencoder/srec/bytearraysrecstreamencoder.cpp b/kasten/gui/io/streamencoder/srec/bytearraysrecstreamencoder.cpp
--- a/kasten/gui/io/streamencoder/srec/bytearraysrecstreamencoder.cpp
+++ b/kasten/gui/io/streamencoder/srec/bytearraysrecstreamencoder.cpp
@@ -189,7 +189,7 @@
             ++recordCount;
             recordOffset = i;
             d = 0;
-            nextDataEnd = qMin(range.end() - i + 1, dataPerLineCount);
+        nextDataEnd = (int)qMin(range.end() - i + 1, (Okteta::Address)dataPerLineCount);
         }
     }
 
diff --git a/kasten/gui/io/streamencoder/uuencoding/bytearrayuuencodingstreamencoder.cpp b/kasten/gui/io/streamencoder/uuencoding/bytearrayuuencodingstreamencoder.cpp
--- a/kasten/gui/io/streamencoder/uuencoding/bytearrayuuencodingstreamencoder.cpp
+++ b/kasten/gui/io/streamencoder/uuencoding/bytearrayuuencodingstreamencoder.cpp
@@ -109,7 +109,7 @@
     // header
     textStream << encodeData->header << " 644 " << mSettings.fileName.toLatin1();
 
-    const int firstLineLength = qMin(range.width(), uuInputLineLength);
+    const int firstLineLength = (int)qMin(range.width(), (Okteta::Size)uuInputLineLength);
     if (firstLineLength > 0) {
         textStream << '\n';
         if (encodeData->hasLength) {
diff --git a/kasten/gui/io/streamencoder/xxencoding/bytearrayxxencodingstreamencoder.cpp b/kasten/gui/io/streamencoder/xxencoding/bytearrayxxencodingstreamencoder.cpp
--- a/kasten/gui/io/streamencoder/xxencoding/bytearrayxxencodingstreamencoder.cpp
+++ b/kasten/gui/io/streamencoder/xxencoding/bytearrayxxencodingstreamencoder.cpp
@@ -90,7 +90,7 @@
     // header
     textStream << header << " 644 " << mSettings.fileName.toLatin1();
 
-    const int firstLineLength = qMin(range.width(), xxInputLineLength);
+    const int firstLineLength = (int)qMin(range.width(), (Okteta::Size)xxInputLineLength);
     if (firstLineLength > 0) {
         textStream << '\n';
         textStream << xxmapByte(firstLineLength);
diff --git a/libs/kasten/core/tests/testdocumentfileloadthread.cpp b/libs/kasten/core/tests/testdocumentfileloadthread.cpp
--- a/libs/kasten/core/tests/testdocumentfileloadthread.cpp
+++ b/libs/kasten/core/tests/testdocumentfileloadthread.cpp
@@ -40,7 +40,7 @@
 void TestDocumentFileLoadThread::run()
 {
     QDataStream inStream(mFile);
-    const int fileSize = mFile->size();
+    const qint64 fileSize = mFile->size();
 
     // test header
     const int headerSize = mHeader.size();
diff --git a/libs/kasten/core/tests/testdocumentfilereloadthread.cpp b/libs/kasten/core/tests/testdocumentfilereloadthread.cpp
--- a/libs/kasten/core/tests/testdocumentfilereloadthread.cpp
+++ b/libs/kasten/core/tests/testdocumentfilereloadthread.cpp
@@ -49,7 +49,7 @@
 void TestDocumentFileReloadThread::run()
 {
     QDataStream inStream(mFile);
-    const int fileSize = mFile->size();
+    const qint64 fileSize = mFile->size();
 
     // test header
     const int headerSize = mHeader.size();