diff --git a/src/AboutDialog.h b/src/AboutDialog.h
index 7eed5c72..3eb5aee9 100644
--- a/src/AboutDialog.h
+++ b/src/AboutDialog.h
@@ -12,7 +12,7 @@ class AboutDialog : public QDialog
     Q_OBJECT
 
 public:
-    explicit AboutDialog(QWidget *parent = 0);
+    explicit AboutDialog(QWidget *parent = nullptr);
     ~AboutDialog();
 
 private:
diff --git a/src/CipherDialog.cpp b/src/CipherDialog.cpp
index 3ca4c0af..51285683 100644
--- a/src/CipherDialog.cpp
+++ b/src/CipherDialog.cpp
@@ -56,8 +56,8 @@ void CipherDialog::checkInputFields()
     {
         if(keyFormat() == KeyFormats::Passphrase)
         {
-            ui->editPassword->setValidator(0);
-            ui->editPassword2->setValidator(0);
+            ui->editPassword->setValidator(nullptr);
+            ui->editPassword2->setValidator(nullptr);
             ui->editPassword->setPlaceholderText("");
         } else if(keyFormat() == KeyFormats::RawKey) {
             ui->editPassword->setValidator(rawKeyValidator);
diff --git a/src/ColumnDisplayFormatDialog.h b/src/ColumnDisplayFormatDialog.h
index 066e348a..d79c7e04 100644
--- a/src/ColumnDisplayFormatDialog.h
+++ b/src/ColumnDisplayFormatDialog.h
@@ -12,7 +12,7 @@ class ColumnDisplayFormatDialog : public QDialog
     Q_OBJECT
 
 public:
-    explicit ColumnDisplayFormatDialog(const QString& colname, QString current_format, QWidget* parent = 0);
+    explicit ColumnDisplayFormatDialog(const QString& colname, QString current_format, QWidget* parent = nullptr);
     ~ColumnDisplayFormatDialog();
 
     QString selectedDisplayFormat() const;
diff --git a/src/DbStructureModel.cpp b/src/DbStructureModel.cpp
index af869b6c..9bb1d2f4 100644
--- a/src/DbStructureModel.cpp
+++ b/src/DbStructureModel.cpp
@@ -249,7 +249,7 @@ bool DbStructureModel::dropMimeData(const QMimeData* data, Qt::DropAction action
         reloadData();
         return true;
     } else {
-        QMessageBox::warning(0, QApplication::applicationName(), m_db.lastError());
+        QMessageBox::warning(nullptr, QApplication::applicationName(), m_db.lastError());
         return false;
     }
 }
diff --git a/src/DbStructureModel.h b/src/DbStructureModel.h
index 691d3a69..83d3446c 100644
--- a/src/DbStructureModel.h
+++ b/src/DbStructureModel.h
@@ -12,7 +12,7 @@ class DbStructureModel : public QAbstractItemModel
     Q_OBJECT
 
 public:
-    explicit DbStructureModel(DBBrowserDB& db, QObject* parent = 0);
+    explicit DbStructureModel(DBBrowserDB& db, QObject* parent = nullptr);
     ~DbStructureModel();
 
     void reloadData();
diff --git a/src/EditDialog.h b/src/EditDialog.h
index cd91d62e..399be289 100644
--- a/src/EditDialog.h
+++ b/src/EditDialog.h
@@ -15,7 +15,7 @@ class EditDialog : public QDialog
     Q_OBJECT
 
 public:
-    explicit EditDialog(QWidget* parent = 0);
+    explicit EditDialog(QWidget* parent = nullptr);
     ~EditDialog();
 
     void setCurrentIndex(const QModelIndex& idx);
diff --git a/src/EditIndexDialog.h b/src/EditIndexDialog.h
index ad6d28b3..75d6c730 100644
--- a/src/EditIndexDialog.h
+++ b/src/EditIndexDialog.h
@@ -17,7 +17,7 @@ class EditIndexDialog : public QDialog
     Q_OBJECT
 
 public:
-    explicit EditIndexDialog(DBBrowserDB& db, const sqlb::ObjectIdentifier& indexName, bool createIndex, QWidget* parent = 0);
+    explicit EditIndexDialog(DBBrowserDB& db, const sqlb::ObjectIdentifier& indexName, bool createIndex, QWidget* parent = nullptr);
     ~EditIndexDialog();
 
 private slots:
diff --git a/src/EditTableDialog.cpp b/src/EditTableDialog.cpp
index 2f974291..ffff932c 100644
--- a/src/EditTableDialog.cpp
+++ b/src/EditTableDialog.cpp
@@ -604,7 +604,7 @@ void EditTableDialog::removeField()
         {
             if(!pdb.renameColumn(curTable, m_table, ui->treeWidget->currentItem()->text(0), sqlb::FieldPtr()))
             {
-                QMessageBox::warning(0, QApplication::applicationName(), pdb.lastError());
+                QMessageBox::warning(nullptr, QApplication::applicationName(), pdb.lastError());
             } else {
                 //relayout
                 m_table = *(pdb.getObjectByName(curTable).dynamicCast<sqlb::Table>());
@@ -688,7 +688,7 @@ void EditTableDialog::moveCurrentField(bool down)
                     (down ? 1 : -1)
                 ))
         {
-            QMessageBox::warning(0, QApplication::applicationName(), pdb.lastError());
+            QMessageBox::warning(nullptr, QApplication::applicationName(), pdb.lastError());
         } else {
             // Reload table SQL
             m_table = *(pdb.getObjectByName(curTable).dynamicCast<sqlb::Table>());
diff --git a/src/EditTableDialog.h b/src/EditTableDialog.h
index 53649773..79b738bc 100644
--- a/src/EditTableDialog.h
+++ b/src/EditTableDialog.h
@@ -18,7 +18,7 @@ class EditTableDialog : public QDialog
     Q_OBJECT
 
 public:
-    explicit EditTableDialog(DBBrowserDB& pdb, const sqlb::ObjectIdentifier& tableName, bool createTable, QWidget* parent = 0);
+    explicit EditTableDialog(DBBrowserDB& pdb, const sqlb::ObjectIdentifier& tableName, bool createTable, QWidget* parent = nullptr);
     ~EditTableDialog();
 
 protected:
diff --git a/src/ExportDataDialog.h b/src/ExportDataDialog.h
index 4971a826..c2db1ced 100644
--- a/src/ExportDataDialog.h
+++ b/src/ExportDataDialog.h
@@ -22,7 +22,7 @@ public:
         ExportFormatJson,
     };
 
-    explicit ExportDataDialog(DBBrowserDB& db, ExportFormats format, QWidget* parent = 0,
+    explicit ExportDataDialog(DBBrowserDB& db, ExportFormats format, QWidget* parent = nullptr,
                               const QString& query = "", const sqlb::ObjectIdentifier& selection = sqlb::ObjectIdentifier());
     ~ExportDataDialog();
 
diff --git a/src/ExportSqlDialog.h b/src/ExportSqlDialog.h
index 3f455e99..8e0b4670 100644
--- a/src/ExportSqlDialog.h
+++ b/src/ExportSqlDialog.h
@@ -14,7 +14,7 @@ class ExportSqlDialog : public QDialog
     Q_OBJECT
 
 public:
-    explicit ExportSqlDialog(DBBrowserDB* db, QWidget* parent = 0, const QString& selection = "");
+    explicit ExportSqlDialog(DBBrowserDB* db, QWidget* parent = nullptr, const QString& selection = "");
     ~ExportSqlDialog();
 
 private slots:
diff --git a/src/ExtendedTableWidget.h b/src/ExtendedTableWidget.h
index 9243aa3e..41ee2aba 100644
--- a/src/ExtendedTableWidget.h
+++ b/src/ExtendedTableWidget.h
@@ -15,7 +15,7 @@ class ExtendedTableWidget : public QTableView
     Q_OBJECT
 
 public:
-    explicit ExtendedTableWidget(QWidget* parent = 0);
+    explicit ExtendedTableWidget(QWidget* parent = nullptr);
 
     FilterTableHeader* filterHeader() { return m_tableHeader; }
 
diff --git a/src/FileDialog.h b/src/FileDialog.h
index b5ca2829..7b19bcaf 100644
--- a/src/FileDialog.h
+++ b/src/FileDialog.h
@@ -8,16 +8,16 @@ class FileDialog : public QFileDialog
     Q_OBJECT
 
 public:
-    static QString getOpenFileName(QWidget* parent = 0, const QString& caption = QString(),
-                                   const QString& filter = QString(), QString* selectedFilter = 0,
+    static QString getOpenFileName(QWidget* parent = nullptr, const QString& caption = QString(),
+                                   const QString& filter = QString(), QString* selectedFilter = nullptr,
                                    Options options = 0);
-    static QStringList getOpenFileNames(QWidget* parent = 0, const QString& caption = QString(),
-                                        const QString& filter = QString(), QString* selectedFilter = 0,
+    static QStringList getOpenFileNames(QWidget* parent = nullptr, const QString& caption = QString(),
+                                        const QString& filter = QString(), QString* selectedFilter = nullptr,
                                         Options options = 0);
-    static QString getSaveFileName(QWidget* parent = 0, const QString& caption = QString(),
-                                   const QString& filter = QString(), const QString& defaultFileName = QString(), QString* selectedFilter = 0,
+    static QString getSaveFileName(QWidget* parent = nullptr, const QString& caption = QString(),
+                                   const QString& filter = QString(), const QString& defaultFileName = QString(), QString* selectedFilter = nullptr,
                                    Options options = 0);
-    static QString getExistingDirectory(QWidget* parent = 0, const QString& caption = QString(),
+    static QString getExistingDirectory(QWidget* parent = nullptr, const QString& caption = QString(),
                                         Options options = 0);
 
     static QString getSqlDatabaseFileFilter()
diff --git a/src/FilterTableHeader.h b/src/FilterTableHeader.h
index 8e170ba3..d8b21292 100644
--- a/src/FilterTableHeader.h
+++ b/src/FilterTableHeader.h
@@ -13,7 +13,7 @@ class FilterTableHeader : public QHeaderView
     Q_OBJECT
 
 public:
-    explicit FilterTableHeader(QTableView* parent = 0);
+    explicit FilterTableHeader(QTableView* parent = nullptr);
     virtual QSize sizeHint() const;
     
 public slots:
diff --git a/src/ImportCsvDialog.h b/src/ImportCsvDialog.h
index 62d5353f..6f48c5d1 100644
--- a/src/ImportCsvDialog.h
+++ b/src/ImportCsvDialog.h
@@ -20,7 +20,7 @@ class ImportCsvDialog : public QDialog
     Q_OBJECT
 
 public:
-    explicit ImportCsvDialog(const QStringList& filenames, DBBrowserDB* db, QWidget* parent = 0);
+    explicit ImportCsvDialog(const QStringList& filenames, DBBrowserDB* db, QWidget* parent = nullptr);
     ~ImportCsvDialog();
 
 private slots:
diff --git a/src/MainWindow.cpp b/src/MainWindow.cpp
index d726bc27..bdad34f4 100644
--- a/src/MainWindow.cpp
+++ b/src/MainWindow.cpp
@@ -430,7 +430,7 @@ void MainWindow::clearTableBrowser()
     if (!ui->dataTable->model())
         return;
 
-    ui->dataTable->setModel(0);
+    ui->dataTable->setModel(nullptr);
     if(qobject_cast<FilterTableHeader*>(ui->dataTable->horizontalHeader()))
         qobject_cast<FilterTableHeader*>(ui->dataTable->horizontalHeader())->generateFilters(0);
 }
@@ -455,7 +455,7 @@ void MainWindow::populateTable()
 
     // Set model
     bool reconnectSelectionSignals = false;
-    if(ui->dataTable->model() == 0)
+    if(ui->dataTable->model() == nullptr)
         reconnectSelectionSignals = true;
     ui->dataTable->setModel(m_browseTableModel);
     if(reconnectSelectionSignals)
@@ -594,7 +594,7 @@ bool MainWindow::fileClose()
     setRecordsetLabel();
 
     // Reset the plot dock model
-    plotDock->updatePlot(0);
+    plotDock->updatePlot(nullptr);
 
     activateFields(false);
 
@@ -2240,7 +2240,7 @@ void MainWindow::editEncryption()
         // Show progress dialog even though we can't provide any detailed progress information but this
         // process might take some time.
         QProgressDialog progress(this);
-        progress.setCancelButton(0);
+        progress.setCancelButton(nullptr);
         progress.setWindowModality(Qt::ApplicationModal);
         progress.show();
         qApp->processEvents();
diff --git a/src/MainWindow.h b/src/MainWindow.h
index 5333aa57..307e3863 100644
--- a/src/MainWindow.h
+++ b/src/MainWindow.h
@@ -94,7 +94,7 @@ class MainWindow : public QMainWindow
     Q_OBJECT
 
 public:
-    explicit MainWindow(QWidget* parent = 0);
+    explicit MainWindow(QWidget* parent = nullptr);
     ~MainWindow();
 
     DBBrowserDB& getDb() { return db; }
diff --git a/src/PlotDock.cpp b/src/PlotDock.cpp
index 2f588b8b..57b298c6 100644
--- a/src/PlotDock.cpp
+++ b/src/PlotDock.cpp
@@ -151,14 +151,14 @@ void PlotDock::updatePlot(SqliteTableModel* model, BrowseDataTableSettings* sett
     }
 
     // search for the x axis select
-    QTreeWidgetItem* xitem = 0;
+    QTreeWidgetItem* xitem = nullptr;
     for(int i = 0; i < ui->treePlotColumns->topLevelItemCount(); ++i)
     {
         xitem = ui->treePlotColumns->topLevelItem(i);
         if(xitem->checkState(PlotColumnX) == Qt::Checked)
             break;
 
-        xitem = 0;
+        xitem = nullptr;
     }
 
     QStringList yAxisLabels;
diff --git a/src/PlotDock.h b/src/PlotDock.h
index 445c88be..b0f1d81b 100644
--- a/src/PlotDock.h
+++ b/src/PlotDock.h
@@ -17,7 +17,7 @@ class PlotDock : public QDialog
     Q_OBJECT
 
 public:
-    explicit PlotDock(QWidget* parent = 0);
+    explicit PlotDock(QWidget* parent = nullptr);
     ~PlotDock();
 
     struct PlotSettings
diff --git a/src/PreferencesDialog.h b/src/PreferencesDialog.h
index 646878db..456f7c27 100644
--- a/src/PreferencesDialog.h
+++ b/src/PreferencesDialog.h
@@ -19,7 +19,7 @@ class PreferencesDialog : public QDialog
     Q_OBJECT
 
 public:
-    explicit PreferencesDialog(QWidget* parent = 0);
+    explicit PreferencesDialog(QWidget* parent = nullptr);
     ~PreferencesDialog();
 
 private slots:
diff --git a/src/RemoteDatabase.cpp b/src/RemoteDatabase.cpp
index 1d375b86..6f4722ef 100644
--- a/src/RemoteDatabase.cpp
+++ b/src/RemoteDatabase.cpp
@@ -103,7 +103,7 @@ void RemoteDatabase::gotReply(QNetworkReply* reply)
     // Check if request was successful
     if(reply->error() != QNetworkReply::NoError)
     {
-        QMessageBox::warning(0, qApp->applicationName(),
+        QMessageBox::warning(nullptr, qApp->applicationName(),
                              tr("Error when connecting to %1.\n%2").arg(reply->url().toString()).arg(reply->errorString()));
         reply->deleteLater();
         return;
@@ -258,7 +258,7 @@ void RemoteDatabase::gotError(QNetworkReply* reply, const QList<QSslError>& erro
 
     // Build an error message and short it to the user
     QString message = tr("Error opening remote file at %1.\n%2").arg(reply->url().toString()).arg(errors.at(0).errorString());
-    QMessageBox::warning(0, qApp->applicationName(), message);
+    QMessageBox::warning(nullptr, qApp->applicationName(), message);
 
     // Delete reply later, i.e. after returning from this slot function
     if(m_progress)
@@ -330,7 +330,7 @@ bool RemoteDatabase::prepareSsl(QNetworkRequest* request, const QString& clientC
     const QSslCertificate& cert = m_clientCertFiles[clientCert];
     if(cert.isNull())
     {
-        QMessageBox::warning(0, qApp->applicationName(), tr("Error: Invalid client certificate specified."));
+        QMessageBox::warning(nullptr, qApp->applicationName(), tr("Error: Invalid client certificate specified."));
         return false;
     }
 
@@ -342,7 +342,7 @@ bool RemoteDatabase::prepareSsl(QNetworkRequest* request, const QString& clientC
     {
         // If the private key couldn't be read, we assume it's password protected. So ask the user for the correct password and try reading it
         // again. If the user cancels the password dialog, abort the whole process.
-        QString password = QInputDialog::getText(0, qApp->applicationName(), tr("Please enter the passphrase for this client certificate in order to authenticate."));
+        QString password = QInputDialog::getText(nullptr, qApp->applicationName(), tr("Please enter the passphrase for this client certificate in order to authenticate."));
         if(password.isEmpty())
             return false;
         clientKey = QSslKey(&fileClientCert, QSsl::Rsa, QSsl::Pem, QSsl::PrivateKey, password.toUtf8());
@@ -389,7 +389,7 @@ void RemoteDatabase::fetch(const QString& url, RequestType type, const QString&
     // Check if network is accessible. If not, abort right here
     if(m_manager->networkAccessible() == QNetworkAccessManager::NotAccessible)
     {
-        QMessageBox::warning(0, qApp->applicationName(), tr("Error: The network is not accessible."));
+        QMessageBox::warning(nullptr, qApp->applicationName(), tr("Error: The network is not accessible."));
         return;
     }
 
@@ -442,7 +442,7 @@ void RemoteDatabase::push(const QString& filename, const QString& url, const QSt
     // Check if network is accessible. If not, abort right here
     if(m_manager->networkAccessible() == QNetworkAccessManager::NotAccessible)
     {
-        QMessageBox::warning(0, qApp->applicationName(), tr("Error: The network is not accessible."));
+        QMessageBox::warning(nullptr, qApp->applicationName(), tr("Error: The network is not accessible."));
         return;
     }
 
@@ -451,7 +451,7 @@ void RemoteDatabase::push(const QString& filename, const QString& url, const QSt
     if(!file->open(QFile::ReadOnly))
     {
         delete file;
-        QMessageBox::warning(0, qApp->applicationName(), tr("Error: Cannot open the file for sending."));
+        QMessageBox::warning(nullptr, qApp->applicationName(), tr("Error: Cannot open the file for sending."));
         return;
     }
 
@@ -591,7 +591,7 @@ QString RemoteDatabase::localAdd(QString filename, QString identity, const QUrl&
         // Insert database into local database list
         QString sql = QString("INSERT INTO local(identity, name, url, commit_id, file) VALUES(?, ?, ?, ?, ?)");
         sqlite3_stmt* stmt;
-        if(sqlite3_prepare_v2(m_dbLocal, sql.toUtf8(), -1, &stmt, 0) != SQLITE_OK)
+        if(sqlite3_prepare_v2(m_dbLocal, sql.toUtf8(), -1, &stmt, nullptr) != SQLITE_OK)
             return QString();
 
         if(sqlite3_bind_text(stmt, 1, identity.toUtf8(), identity.toUtf8().length(), SQLITE_TRANSIENT))
@@ -644,7 +644,7 @@ QString RemoteDatabase::localAdd(QString filename, QString identity, const QUrl&
 
         QString sql = QString("UPDATE local SET commit_id=? WHERE identity=? AND url=?");
         sqlite3_stmt* stmt;
-        if(sqlite3_prepare_v2(m_dbLocal, sql.toUtf8(), -1, &stmt, 0) != SQLITE_OK)
+        if(sqlite3_prepare_v2(m_dbLocal, sql.toUtf8(), -1, &stmt, nullptr) != SQLITE_OK)
             return QString();
 
         if(sqlite3_bind_text(stmt, 1, new_commit_id.toUtf8(), new_commit_id.toUtf8().length(), SQLITE_TRANSIENT))
@@ -694,7 +694,7 @@ QString RemoteDatabase::localExists(const QUrl& url, QString identity)
     // Query commit id and filename for the given combination of url and identity
     QString sql = QString("SELECT id, commit_id, file FROM local WHERE url=? AND identity=?");
     sqlite3_stmt* stmt;
-    if(sqlite3_prepare_v2(m_dbLocal, sql.toUtf8(), -1, &stmt, 0) != SQLITE_OK)
+    if(sqlite3_prepare_v2(m_dbLocal, sql.toUtf8(), -1, &stmt, nullptr) != SQLITE_OK)
         return QString();
 
     if(sqlite3_bind_text(stmt, 1, url.toString(QUrl::PrettyDecoded | QUrl::RemoveQuery).toUtf8(), url.toString(QUrl::PrettyDecoded | QUrl::RemoveQuery).toUtf8().length(), SQLITE_TRANSIENT))
@@ -757,7 +757,7 @@ QString RemoteDatabase::localExists(const QUrl& url, QString identity)
             // files are all in the same directory and their names need to be unique because of this.
             QString sql = QString("DELETE FROM local WHERE file=?");
             sqlite3_stmt* stmt;
-            if(sqlite3_prepare_v2(m_dbLocal, sql.toUtf8(), -1, &stmt, 0) != SQLITE_OK)
+            if(sqlite3_prepare_v2(m_dbLocal, sql.toUtf8(), -1, &stmt, nullptr) != SQLITE_OK)
                 return QString();
             if(sqlite3_bind_text(stmt, 1, local_file.toUtf8(), local_file.toUtf8().length(), SQLITE_TRANSIENT))
             {
@@ -795,7 +795,7 @@ QString RemoteDatabase::localCheckFile(const QString& local_file)
         // be unique for the entire table because the files are all in the same directory and their names need to be unique because of this.
         QString sql = QString("DELETE FROM local WHERE file=?");
         sqlite3_stmt* stmt;
-        if(sqlite3_prepare_v2(m_dbLocal, sql.toUtf8(), -1, &stmt, 0) != SQLITE_OK)
+        if(sqlite3_prepare_v2(m_dbLocal, sql.toUtf8(), -1, &stmt, nullptr) != SQLITE_OK)
             return QString();
         if(sqlite3_bind_text(stmt, 1, local_file.toUtf8(), local_file.toUtf8().length(), SQLITE_TRANSIENT))
         {
diff --git a/src/SqlUiLexer.h b/src/SqlUiLexer.h
index 2f21277c..b356ceaa 100644
--- a/src/SqlUiLexer.h
+++ b/src/SqlUiLexer.h
@@ -12,7 +12,7 @@ class SqlUiLexer : public QsciLexerSQL
     Q_OBJECT
 
 public:
-    explicit SqlUiLexer(QObject *parent = 0);
+    explicit SqlUiLexer(QObject *parent = nullptr);
 
     enum ApiCompleterIconId
     {
diff --git a/src/VacuumDialog.h b/src/VacuumDialog.h
index 7ba8cba7..f828d431 100644
--- a/src/VacuumDialog.h
+++ b/src/VacuumDialog.h
@@ -14,7 +14,7 @@ class VacuumDialog : public QDialog
     Q_OBJECT
 
 public:
-    explicit VacuumDialog(DBBrowserDB* _db, QWidget* parent = 0);
+    explicit VacuumDialog(DBBrowserDB* _db, QWidget* parent = nullptr);
     ~VacuumDialog();
 
 private:
diff --git a/src/csvparser.cpp b/src/csvparser.cpp
index e7841054..ff0be680 100644
--- a/src/csvparser.cpp
+++ b/src/csvparser.cpp
@@ -6,7 +6,7 @@ CSVParser::CSVParser(bool trimfields, char fieldseparator, char quotechar)
     : m_bTrimFields(trimfields)
     , m_cFieldSeparator(fieldseparator)
     , m_cQuoteChar(quotechar)
-    , m_pCSVProgress(0)
+    , m_pCSVProgress(nullptr)
     , m_nBufferSize(4096)
 {
 }
@@ -120,7 +120,7 @@ CSVParser::ParserResult CSVParser::parse(csvRowFunction insertFunction, QTextStr
         m_pCSVProgress->start();
 
     // Initialise row buffer and get pointer to the first field
-    record = { 0, 0, 0 };
+    record = { nullptr, 0, 0 };
     increaseRowSize(record);
     field = record.fields;
 
diff --git a/src/sqlitedb.cpp b/src/sqlitedb.cpp
index 1d1a4b1c..a5a7ce28 100644
--- a/src/sqlitedb.cpp
+++ b/src/sqlitedb.cpp
@@ -87,7 +87,7 @@ static void regexp(sqlite3_context* ctx, int /*argc*/, sqlite3_value* argv[])
 
 bool DBBrowserDB::isOpen ( ) const
 {
-    return _db!=0;
+    return _db != nullptr;
 }
 
 bool DBBrowserDB::getDirty() const
@@ -103,7 +103,7 @@ bool DBBrowserDB::open(const QString& db, bool readOnly)
     dontCheckForStructureUpdates = false;
 
     // Get encryption settings for database file
-    CipherDialog* cipher = 0;
+    CipherDialog* cipher = nullptr;
     if(tryEncryptionSettings(db, &isEncrypted, cipher) == false)
         return false;
 
@@ -128,9 +128,9 @@ bool DBBrowserDB::open(const QString& db, bool readOnly)
     if (_db)
     {
         // add UTF16 collation (comparison is performed by QString functions)
-        sqlite3_create_collation(_db, "UTF16", SQLITE_UTF16, 0, sqlite_compare_utf16);
+        sqlite3_create_collation(_db, "UTF16", SQLITE_UTF16, nullptr, sqlite_compare_utf16);
         // add UTF16CI (case insensitive) collation (comparison is performed by QString functions)
-        sqlite3_create_collation(_db, "UTF16CI", SQLITE_UTF16, 0, sqlite_compare_utf16ci);
+        sqlite3_create_collation(_db, "UTF16CI", SQLITE_UTF16, nullptr, sqlite_compare_utf16ci);
        
         // register collation callback
         Callback<void(void*, sqlite3*, int, const char*)>::func = std::bind(&DBBrowserDB::collationNeeded, this, std::placeholders::_1, std::placeholders::_2, std::placeholders::_3, std::placeholders::_4);
@@ -187,7 +187,7 @@ bool DBBrowserDB::attach(const QString& filename, QString attach_as)
             if(fi == path)
             {
                 QString schema = QString::fromUtf8((const char*)sqlite3_column_text(db_vm, 1));
-                QMessageBox::information(0, qApp->applicationName(), tr("This database has already been attached. Its schema name is '%1'.").arg(schema));
+                QMessageBox::information(nullptr, qApp->applicationName(), tr("This database has already been attached. Its schema name is '%1'.").arg(schema));
                 return false;
             }
         }
@@ -195,7 +195,7 @@ bool DBBrowserDB::attach(const QString& filename, QString attach_as)
 
     // Ask for name to be given to the attached database if none was provided
     if(attach_as.isEmpty())
-        attach_as = QInputDialog::getText(0,
+        attach_as = QInputDialog::getText(nullptr,
                                           qApp->applicationName(),
                                           tr("Please specify the database name under which you want to access the attached database"),
                                           QLineEdit::Normal,
@@ -206,7 +206,7 @@ bool DBBrowserDB::attach(const QString& filename, QString attach_as)
 
 #ifdef ENABLE_SQLCIPHER
     // Try encryption settings
-    CipherDialog* cipher = 0;
+    CipherDialog* cipher = nullptr;
     bool is_encrypted;
     if(tryEncryptionSettings(filename, &is_encrypted, cipher) == false)
         return false;
@@ -217,14 +217,14 @@ bool DBBrowserDB::attach(const QString& filename, QString attach_as)
         key = "KEY " + cipher->password();
     if(!executeSQL(QString("ATTACH '%1' AS %2 %3").arg(filename).arg(sqlb::escapeIdentifier(attach_as)).arg(key), false))
     {
-        QMessageBox::warning(0, qApp->applicationName(), lastErrorMessage);
+        QMessageBox::warning(nullptr, qApp->applicationName(), lastErrorMessage);
         return false;
     }
     if(cipher && cipher->pageSize() != 1024)
     {
         if(!executeSQL(QString("PRAGMA %1.cipher_page_size = %2").arg(sqlb::escapeIdentifier(attach_as)).arg(cipher->pageSize()), false))
         {
-            QMessageBox::warning(0, qApp->applicationName(), lastErrorMessage);
+            QMessageBox::warning(nullptr, qApp->applicationName(), lastErrorMessage);
             return false;
         }
     }
@@ -232,7 +232,7 @@ bool DBBrowserDB::attach(const QString& filename, QString attach_as)
     // Attach database
     if(!executeSQL(QString("ATTACH '%1' AS %2").arg(filename).arg(sqlb::escapeIdentifier(attach_as)), false))
     {
-        QMessageBox::warning(0, qApp->applicationName(), lastErrorMessage);
+        QMessageBox::warning(nullptr, qApp->applicationName(), lastErrorMessage);
         return false;
     }
 #endif
@@ -254,7 +254,7 @@ bool DBBrowserDB::tryEncryptionSettings(const QString& filename, bool* encrypted
 
     // Try reading from database
     *encrypted = false;
-    cipherSettings = 0;
+    cipherSettings = nullptr;
     while(true)
     {
         QString statement = "SELECT COUNT(*) FROM sqlite_master;";
@@ -274,7 +274,7 @@ bool DBBrowserDB::tryEncryptionSettings(const QString& filename, bool* encrypted
             sqlite3_finalize(vm);
 #ifdef ENABLE_SQLCIPHER
             delete cipherSettings;
-            cipherSettings = new CipherDialog(0, false);
+            cipherSettings = new CipherDialog(nullptr, false);
             if(cipherSettings->exec())
             {
                 // Close and reopen database first to be in a clean state after the failed read attempt from above
@@ -282,7 +282,7 @@ bool DBBrowserDB::tryEncryptionSettings(const QString& filename, bool* encrypted
                 if(sqlite3_open_v2(filename.toUtf8(), &dbHandle, SQLITE_OPEN_READONLY, NULL) != SQLITE_OK)
                 {
                     delete cipherSettings;
-                    cipherSettings = 0;
+                    cipherSettings = nullptr;
                     return false;
                 }
 
@@ -296,7 +296,7 @@ bool DBBrowserDB::tryEncryptionSettings(const QString& filename, bool* encrypted
                 sqlite3_close(dbHandle);
                 *encrypted = false;
                 delete cipherSettings;
-                cipherSettings = 0;
+                cipherSettings = nullptr;
                 return false;
             }
 #else
@@ -411,7 +411,7 @@ bool DBBrowserDB::create ( const QString & db)
     if( openresult != SQLITE_OK ){
         lastErrorMessage = QString::fromUtf8((const char*)sqlite3_errmsg(_db));
         sqlite3_close(_db);
-        _db = 0;
+        _db = nullptr;
         return false;
     }
 
@@ -459,7 +459,7 @@ bool DBBrowserDB::close()
     {
         if (getDirty())
         {
-            QMessageBox::StandardButton reply = QMessageBox::question(0,
+            QMessageBox::StandardButton reply = QMessageBox::question(nullptr,
                                                                       QApplication::applicationName(),
                                                                       tr("Do you want to save the changes "
                                                                          "made to the database file %1?").arg(curDBFilename),
@@ -477,7 +477,7 @@ bool DBBrowserDB::close()
         }
         sqlite3_close(_db);
     }
-    _db = 0;
+    _db = nullptr;
     schemata.clear();
     savepointList.clear();
     emit dbChanged(getDirty());
@@ -1031,7 +1031,7 @@ bool DBBrowserDB::updateRecord(const sqlb::ObjectIdentifier& table, const QStrin
 
     sqlite3_stmt* stmt;
     int success = 1;
-    if(sqlite3_prepare_v2(_db, sql.toUtf8(), -1, &stmt, 0) != SQLITE_OK)
+    if(sqlite3_prepare_v2(_db, sql.toUtf8(), -1, &stmt, nullptr) != SQLITE_OK)
         success = 0;
     if(success == 1) {
         if(itsBlob)
@@ -1274,9 +1274,9 @@ bool DBBrowserDB::renameColumn(const sqlb::ObjectIdentifier& tablename, const sq
     }
     if(!errored_sqls.isEmpty())
     {
-        QMessageBox::information(0, qApp->applicationName(), tr("Restoring some of the objects associated with this table failed. "
-                                                                "This is most likely because some column names changed. "
-                                                                "Here's the SQL statement which you might want to fix and execute manually:\n\n")
+        QMessageBox::information(nullptr, qApp->applicationName(), tr("Restoring some of the objects associated with this table failed. "
+                                                                      "This is most likely because some column names changed. "
+                                                                      "Here's the SQL statement which you might want to fix and execute manually:\n\n")
                                  + errored_sqls);
     }
 
@@ -1553,7 +1553,7 @@ bool DBBrowserDB::loadExtension(const QString& filename)
 
     // Try to load extension
     char* error;
-    if(sqlite3_load_extension(_db, filename.toUtf8(), 0, &error) == SQLITE_OK)
+    if(sqlite3_load_extension(_db, filename.toUtf8(), nullptr, &error) == SQLITE_OK)
     {
         return true;
     } else {
diff --git a/src/sqlitedb.h b/src/sqlitedb.h
index 1b19f824..88dc0d0e 100644
--- a/src/sqlitedb.h
+++ b/src/sqlitedb.h
@@ -26,7 +26,7 @@ class DBBrowserDB : public QObject
     Q_OBJECT
 
 public:
-    explicit DBBrowserDB () : _db(0), isEncrypted(false), isReadOnly(false), dontCheckForStructureUpdates(false) {}
+    explicit DBBrowserDB () : _db(nullptr), isEncrypted(false), isReadOnly(false), dontCheckForStructureUpdates(false) {}
     virtual ~DBBrowserDB (){}
     bool open(const QString& db, bool readOnly = false);
     bool attach(const QString& filename, QString attach_as = "");
diff --git a/src/sqlitetablemodel.cpp b/src/sqlitetablemodel.cpp
index ea01bb94..483cd37d 100644
--- a/src/sqlitetablemodel.cpp
+++ b/src/sqlitetablemodel.cpp
@@ -368,7 +368,7 @@ bool SqliteTableModel::setTypedData(const QModelIndex& index, bool isBlob, const
             return true;
         } else {
             lock.unlock();
-            QMessageBox::warning(0, qApp->applicationName(), tr("Error changing data:\n%1").arg(m_db.lastError()));
+            QMessageBox::warning(nullptr, qApp->applicationName(), tr("Error changing data:\n%1").arg(m_db.lastError()));
             return false;
         }
     }
diff --git a/src/sqlitetablemodel.h b/src/sqlitetablemodel.h
index 1734a214..7eb7cc6f 100644
--- a/src/sqlitetablemodel.h
+++ b/src/sqlitetablemodel.h
@@ -19,7 +19,7 @@ class SqliteTableModel : public QAbstractTableModel
 #endif
 
 public:
-    explicit SqliteTableModel(DBBrowserDB& db, QObject *parent = 0, size_t chunkSize = 50000, const QString& encoding = QString());
+    explicit SqliteTableModel(DBBrowserDB& db, QObject *parent = nullptr, size_t chunkSize = 50000, const QString& encoding = QString());
     void reset();
 
     int rowCount(const QModelIndex &parent = QModelIndex()) const;
diff --git a/src/sqltextedit.cpp b/src/sqltextedit.cpp
index b516f9f9..50f430b7 100644
--- a/src/sqltextedit.cpp
+++ b/src/sqltextedit.cpp
@@ -8,13 +8,13 @@
 #include <QMimeData>
 #include <cmath>
 
-SqlUiLexer* SqlTextEdit::sqlLexer = 0;
+SqlUiLexer* SqlTextEdit::sqlLexer = nullptr;
 
 SqlTextEdit::SqlTextEdit(QWidget* parent) :
     QsciScintilla(parent)
 {
     // Create lexer object if not done yet
-    if(sqlLexer == 0)
+    if(sqlLexer == nullptr)
         sqlLexer = new SqlUiLexer(this);
 
     // Set the lexer
diff --git a/src/sqltextedit.h b/src/sqltextedit.h
index 4948b448..783a7728 100644
--- a/src/sqltextedit.h
+++ b/src/sqltextedit.h
@@ -14,7 +14,7 @@ class SqlTextEdit : public QsciScintilla
     Q_OBJECT
 
 public:
-    explicit SqlTextEdit(QWidget *parent = 0);
+    explicit SqlTextEdit(QWidget *parent = nullptr);
     virtual ~SqlTextEdit();
 
     static SqlUiLexer* sqlLexer;