diff --git a/connect_gui.py b/connect_gui.py
index 998da25..1ef3183 100644
--- a/connect_gui.py
+++ b/connect_gui.py
@@ -7,3 +7,4 @@ def connect_gui(app):
     app.gui.QTMainWindow.closeEvent = app.utils.on_close
     app.gui.main_window.menuSettings.triggered.connect(app.gui.main_window.settingsDock.show)
     app.gui.main_window.bitsAreSquaresSetting.stateChanged.connect(app.utils.update_font_in_all_bit_editors)
+    app.gui.main_window.highlightOnesSetting.stateChanged.connect(app.utils.update_font_in_all_bit_editors)
diff --git a/gui/raw_ui/main_window.ui b/gui/raw_ui/main_window.ui
index da95905..d90abb6 100644
--- a/gui/raw_ui/main_window.ui
+++ b/gui/raw_ui/main_window.ui
@@ -66,6 +66,18 @@
    <property name="enabled">
     <bool>true</bool>
    </property>
+   <property name="sizePolicy">
+    <sizepolicy hsizetype="Preferred" vsizetype="Preferred">
+     <horstretch>0</horstretch>
+     <verstretch>0</verstretch>
+    </sizepolicy>
+   </property>
+   <property name="minimumSize">
+    <size>
+     <width>200</width>
+     <height>124</height>
+    </size>
+   </property>
    <property name="accessibleName">
     <string/>
    </property>
@@ -88,10 +100,22 @@
     <layout class="QVBoxLayout" name="verticalLayout">
      <item>
       <widget class="QTabWidget" name="settingsTabs">
+       <property name="sizePolicy">
+        <sizepolicy hsizetype="Expanding" vsizetype="Expanding">
+         <horstretch>0</horstretch>
+         <verstretch>0</verstretch>
+        </sizepolicy>
+       </property>
        <property name="currentIndex">
         <number>0</number>
        </property>
        <widget class="QWidget" name="appearanceSettingsTab">
+        <property name="sizePolicy">
+         <sizepolicy hsizetype="Preferred" vsizetype="Preferred">
+          <horstretch>0</horstretch>
+          <verstretch>0</verstretch>
+         </sizepolicy>
+        </property>
         <property name="accessibleName">
          <string/>
         </property>
@@ -101,18 +125,35 @@
         <attribute name="title">
          <string>Appearance</string>
         </attribute>
-        <layout class="QVBoxLayout" name="verticalLayout_2">
-         <item>
-          <widget class="QCheckBox" name="bitsAreSquaresSetting">
-           <property name="text">
-            <string>Bits are squares</string>
-           </property>
-           <property name="tristate">
-            <bool>false</bool>
-           </property>
-          </widget>
-         </item>
-        </layout>
+        <widget class="QCheckBox" name="highlightOnesSetting">
+         <property name="geometry">
+          <rect>
+           <x>10</x>
+           <y>10</y>
+           <width>111</width>
+           <height>21</height>
+          </rect>
+         </property>
+         <property name="text">
+          <string>Highlight ones</string>
+         </property>
+        </widget>
+        <widget class="QCheckBox" name="bitsAreSquaresSetting">
+         <property name="geometry">
+          <rect>
+           <x>10</x>
+           <y>30</y>
+           <width>119</width>
+           <height>21</height>
+          </rect>
+         </property>
+         <property name="text">
+          <string>Bits are squares</string>
+         </property>
+         <property name="tristate">
+          <bool>false</bool>
+         </property>
+        </widget>
        </widget>
       </widget>
      </item>
diff --git a/main.py b/main.py
index 2b38f13..36b9777 100755
--- a/main.py
+++ b/main.py
@@ -12,11 +12,13 @@ class BreadEditor:
     def __init__(self):
         self.settings = load_dataclass_json(Settings, "settings.json")
         setattr(self.settings, "save", lambda: save_dataclass_json(self.settings, "settings.json"))
+        print(self.settings.highlight_ones)
 
         # save the file module to a variable because we need to use it in other classes but we change some file class --
         # variables that also need to be accesible from the other classes.
         self.file = file
         File = file.File
+
         self.utils = Utils(self)
         self.file_actions = file.FileActions(self)
         self.gui = GUI(self)
diff --git a/settings.py b/settings.py
index 47bf7f9..532cb30 100644
--- a/settings.py
+++ b/settings.py
@@ -7,4 +7,5 @@ from dataclasses import dataclass
 @dataclass
 class Settings:
     last_opened_file: str=f"{os.path.dirname(os.path.abspath(__file__))}/example.txt"
+    highlight_ones: bool=False
     square_bits: bool=False
diff --git a/ui.py b/ui.py
index 1a9d7aa..b863a21 100644
--- a/ui.py
+++ b/ui.py
@@ -29,3 +29,13 @@ class GUI:
         spacing = 200 if self.app.settings.square_bits else 100
 
         self.app.file.BitEditor.font.setLetterSpacing(QFont.SpacingType.PercentageSpacing, spacing)
+
+        print(self.app.settings.highlight_ones)
+        self.main_window.highlightOnesSetting.setChecked(self.app.settings.highlight_ones)
+
+        for file_path in self.app.open_files:
+            editor = self.app.open_files[file_path].bit_editor
+
+            highlighter_document = editor.input.document() if self.app.settings.highlight_ones else None
+
+            editor.bit_highlighter.setDocument(highlighter_document)
diff --git a/utils.py b/utils.py
index 0d959a8..0723f74 100644
--- a/utils.py
+++ b/utils.py
@@ -88,12 +88,19 @@ class Utils:
         self.app.settings.save()
 
     def update_font_in_all_bit_editors(self):
+        self.app.settings.highlight_ones = self.app.gui.main_window.highlightOnesSetting.isChecked()
         self.app.settings.square_bits = self.app.gui.main_window.bitsAreSquaresSetting.isChecked()
 
         for file_path in self.app.open_files:
             editor = self.app.open_files[file_path].bit_editor
 
-            square = self.app.gui.main_window.bitsAreSquaresSetting.isChecked()
+            highlight_ones = self.app.settings.highlight_ones
+
+            highlighter_document = editor.input.document() if highlight_ones else None
+
+            editor.bit_highlighter.setDocument(highlighter_document)
+
+            square = self.app.settings.square_bits
 
             spacing = 200 if square else 100  # add spacing when setting is checked