diff --git a/pageenhancementsdockwidget.cpp b/pageenhancementsdockwidget.cpp
index 73d3bc7..9108c03 100644
--- a/pageenhancementsdockwidget.cpp
+++ b/pageenhancementsdockwidget.cpp
@@ -25,6 +25,7 @@
 #include <QLineEdit>
 #include <QMap>
 #include <QPair>
+#include <QRegExpValidator>
 #include <QSpinBox>
 #include <QString>
 
@@ -114,6 +115,8 @@ PageEnhancementsDockWidget::PageEnhancementsDockWidget(TeletextWidget *parent):
 	level3p5OnlyLabel->setAlignment(Qt::AlignCenter);
 	x27Layout->addWidget(level3p5OnlyLabel, 5, 0, 1, 5);
 
+	m_pageNumberValidator = new QRegExpValidator(QRegExp("[1-8][0-9A-Fa-f][0-9A-Fa-f]"), this);
+
 	for (int i=0; i<8; i++) {
 		if (i < 4) {
 			// Required at which Levels
@@ -136,8 +139,8 @@ PageEnhancementsDockWidget::PageEnhancementsDockWidget(TeletextWidget *parent):
 		// Page link
 		m_composeLinkPageNumberLineEdit[i] = new QLineEdit("100");
 		m_composeLinkPageNumberLineEdit[i]->setMaxLength(3);
-		m_composeLinkPageNumberLineEdit[i]->setInputMask("DHH");
-		// TODO restrict first digit of page number to 1-8
+		m_composeLinkPageNumberLineEdit[i]->setInputMask(">DHH");
+		m_composeLinkPageNumberLineEdit[i]->setValidator(m_pageNumberValidator);
 		x27Layout->addWidget(m_composeLinkPageNumberLineEdit[i], i+(i<4 ? 1 : 2), 3, 1, 1);
 		connect(m_composeLinkPageNumberLineEdit[i], &QLineEdit::textEdited, [=](QString value) { setComposeLinkPageNumber(i, value); } );
 
diff --git a/pageenhancementsdockwidget.h b/pageenhancementsdockwidget.h
index 9927474..7650db4 100644
--- a/pageenhancementsdockwidget.h
+++ b/pageenhancementsdockwidget.h
@@ -24,6 +24,7 @@
 #include <QComboBox>
 #include <QDockWidget>
 #include <QLineEdit>
+#include <QRegExpValidator>
 #include <QSpinBox>
 #include <QString>
 
@@ -51,6 +52,8 @@ private:
 	QCheckBox *m_composeLinkLevelCheckbox[4][2]; // For links 0-3
 	QComboBox *m_composeLinkFunctionComboBox[4]; // For links 4-7; remember to subtract 4!
 	QLineEdit *m_composeLinkPageNumberLineEdit[8], *m_composeLinkSubPageNumbersLineEdit[8];
+
+	QRegExpValidator *m_pageNumberValidator;
 };
 
 #endif
diff --git a/pageoptionsdockwidget.cpp b/pageoptionsdockwidget.cpp
index a73c003..21dccbf 100644
--- a/pageoptionsdockwidget.cpp
+++ b/pageoptionsdockwidget.cpp
@@ -24,6 +24,7 @@
 #include <QHBoxLayout>
 #include <QLabel>
 #include <QLineEdit>
+#include <QRegExpValidator>
 #include <QSpinBox>
 #include <QVBoxLayout>
 
@@ -40,12 +41,14 @@ PageOptionsDockWidget::PageOptionsDockWidget(TeletextWidget *parent): QDockWidge
 	this->setWindowTitle("Page options");
 
 	// Page number
+	m_pageNumberValidator = new QRegExpValidator(QRegExp("[1-8][0-9A-Fa-f][0-9A-Fa-f]"), this);
+
 	QHBoxLayout *pageNumberLayout = new QHBoxLayout;
 	pageNumberLayout->addWidget(new QLabel(tr("Page number")));
 	m_pageNumberEdit = new QLineEdit("100");
 	m_pageNumberEdit->setMaxLength(3);
-	m_pageNumberEdit->setInputMask("DHH");
-	//TODO restrict first digit of page number to 1-8
+	m_pageNumberEdit->setInputMask(">DHH");
+	m_pageNumberEdit->setValidator(m_pageNumberValidator);
 	pageNumberLayout->addWidget(m_pageNumberEdit);
 	connect(m_pageNumberEdit, &QLineEdit::textEdited, m_parentMainWidget->document(), &TeletextDocument::setPageNumberFromString);
 
@@ -66,8 +69,8 @@ PageOptionsDockWidget::PageOptionsDockWidget(TeletextWidget *parent): QDockWidge
 		fastTextLayout->addWidget(new QLabel(fastTextLabel[i]), 0, i, 1, 1, Qt::AlignCenter);
 		m_fastTextEdit[i] = new QLineEdit;
 		m_fastTextEdit[i]->setMaxLength(3);
-		m_fastTextEdit[i]->setInputMask("DHH");
-		//TODO restrict first digit of page number to 1-8
+		m_fastTextEdit[i]->setInputMask(">DHH");
+		m_fastTextEdit[i]->setValidator(m_pageNumberValidator);
 		fastTextLayout->addWidget(m_fastTextEdit[i], 1, i, 1, 1);
 		connect(m_fastTextEdit[i], &QLineEdit::textEdited, [=](QString value) { setFastTextLinkPageNumber(i, value); } );
 	}
diff --git a/pageoptionsdockwidget.h b/pageoptionsdockwidget.h
index 84fc89f..7827534 100644
--- a/pageoptionsdockwidget.h
+++ b/pageoptionsdockwidget.h
@@ -24,6 +24,7 @@
 #include <QComboBox>
 #include <QDockWidget>
 #include <QLineEdit>
+#include <QRegExpValidator>
 #include <QSpinBox>
 
 #include "mainwidget.h"
@@ -45,6 +46,8 @@ private:
 	QComboBox *m_defaultRegionCombo, *m_defaultNOSCombo, *m_secondRegionCombo, *m_secondNOSCombo;
 	QLineEdit *m_fastTextEdit[6];
 
+	QRegExpValidator *m_pageNumberValidator;
+
 	void addRegionList(QComboBox *);
 	void setFastTextLinkPageNumber(int, const QString &);
 	void setDefaultRegion();