diff --git a/Life/App.xaml b/Life/App.xaml
index 28bcbde..0dc76a5 100644
--- a/Life/App.xaml
+++ b/Life/App.xaml
@@ -7,12 +7,11 @@
          <Style x:Key="Header" TargetType="TextBlock">
              <Setter Property="FontSize" Value="16" />
              <Setter Property="FontWeight" Value="Medium"/>
-             <Setter Property="Margin" Value="0 0 0 0"/>
+             <Setter Property="Margin" Value="0 0 18 0"/>
          </Style>
          <Style x:Key="Value" TargetType="TextBlock">
              <Setter Property="FontSize" Value="24" />
              <Setter Property="FontWeight" Value="Black"/>
-             <Setter Property="Margin" Value="18 0 0 0"></Setter>
          </Style>
     </Application.Resources>
 </Application>
diff --git a/Life/Automaton/BasicField.cs b/Life/Automaton/BasicField.cs
index f2afbda..ac32053 100644
--- a/Life/Automaton/BasicField.cs
+++ b/Life/Automaton/BasicField.cs
@@ -24,7 +24,7 @@ namespace Life.Automaton
         
         private Cell[,] _cells;
 
-        public Size Size { get; }
+        public Size Size { get; private set; }
 
         public Cell this[int x, int y]
         {
@@ -52,6 +52,20 @@ namespace Life.Automaton
             _observers.ForEach(observer => observer.OnNext(this));
         }
 
+        public void Resize(int width, int height)
+        {
+            var cells = new Cell[width, height];
+            
+            for (int x = 0; x < width; x++)
+                for (int y = 0; y < height; y++)
+                    cells[x, y] = (x >= Size.Width || y >= Size.Height) ? new Cell() : _cells[x, y];
+            
+            Size = new Size(width, height);
+            _cells = cells;
+            
+            Notify();
+        }
+
         public IDisposable Subscribe(IObserver<IField> observer)
         {
             _observers.Add(observer);
diff --git a/Life/Automaton/IField.cs b/Life/Automaton/IField.cs
index 6b25e1d..1107314 100644
--- a/Life/Automaton/IField.cs
+++ b/Life/Automaton/IField.cs
@@ -18,5 +18,7 @@ namespace Life.Automaton
 
         void Transform(Rule rule);
         void Notify();
+
+        void Resize(int width, int height);
     }
 }
\ No newline at end of file
diff --git a/Life/AutomatonField.xaml.cs b/Life/AutomatonField.xaml.cs
index afe1d5a..a7dd19f 100644
--- a/Life/AutomatonField.xaml.cs
+++ b/Life/AutomatonField.xaml.cs
@@ -64,13 +64,13 @@ namespace Life
         
         #region Dependency Properties
         public static readonly DependencyProperty SizeProperty = DependencyProperty.Register(
-            "Size", 
+            nameof(Size), 
             typeof(int), typeof(AutomatonField),
              new PropertyMetadata(OnSizeChanged)
         );
         
         public static readonly DependencyProperty SeparationProperty = DependencyProperty.Register(
-            "Separation", 
+            nameof(Separation), 
             typeof(int), typeof(AutomatonField),
             new PropertyMetadata(OnSeparationChanged)
         );
@@ -80,7 +80,7 @@ namespace Life
             typeof(IField), typeof(AutomatonField),
             new PropertyMetadata(OnFieldChanged)
         );
-        
+
         public static readonly DependencyProperty ClickCommandProperty = DependencyProperty.Register(
             nameof(ClickCommand), 
             typeof(ICommand), typeof(AutomatonField)
diff --git a/Life/MainWindow.xaml b/Life/MainWindow.xaml
index 8d9aa62..0352c0b 100644
--- a/Life/MainWindow.xaml
+++ b/Life/MainWindow.xaml
@@ -30,23 +30,27 @@
             <GridSplitter Grid.Column="1" Width="3" ResizeDirection="Columns" ResizeBehavior="PreviousAndNext"/>
             
             <StackPanel Orientation="Vertical" Margin="8" Grid.Column="2" HorizontalAlignment="Stretch">
-                <DockPanel HorizontalAlignment="Stretch"> 
-                    <TextBlock Style="{StaticResource Header}" VerticalAlignment="Center">Iteracja</TextBlock>
+                <DockPanel HorizontalAlignment="Stretch" Margin="0 0 0 8"> 
+                    <TextBlock Style="{StaticResource Header}" VerticalAlignment="Center">Iteration</TextBlock>
                     <TextBlock Style="{StaticResource Value}" Text="{Binding Iteration}" VerticalAlignment="Stretch"/>
                     <Button VerticalAlignment="Center" Command="{Binding StepCommand}" HorizontalAlignment="Right">
-                        <TextBlock Margin="4">krok</TextBlock>
+                        <TextBlock Margin="4">step</TextBlock>
+                    </Button>
+                </DockPanel>
+                <DockPanel HorizontalAlignment="Stretch" Margin="0 0 0 8"> 
+                    <TextBlock Style="{StaticResource Header}" VerticalAlignment="Center" DockPanel.Dock="Left">Size</TextBlock>
+                    <StackPanel Orientation="Horizontal" HorizontalAlignment="Stretch" VerticalAlignment="Center">
+                        <TextBox Text="{Binding Width, Mode=TwoWay}"/>
+                        <TextBlock Text=" x "/>
+                        <TextBox Text="{Binding Height, Mode=TwoWay}"/>
+                    </StackPanel>
+                    <Button VerticalAlignment="Center" Command="{Binding ChangeSizeCommand}" DockPanel.Dock="Right" HorizontalAlignment="Right">
+                        <TextBlock Margin="2">change</TextBlock>
                     </Button>
                 </DockPanel>
                 <DockPanel HorizontalAlignment="Stretch"> 
-                    <TextBlock Style="{StaticResource Header}" VerticalAlignment="Center">Rozmiar</TextBlock>
-                    <StackPanel Orientation="Horizontal" HorizontalAlignment="center" VerticalAlignment="Center">
-                        <TextBox Text="{Binding Field.Size.Width, Mode=OneWay}"/>
-                        <TextBlock Text=" x "/>
-                        <TextBox Text="{Binding Field.Size.Height, Mode=OneWay}"/>
-                    </StackPanel>
-                    <Button VerticalAlignment="Center" Command="{Binding StepCommand}" HorizontalAlignment="Right">
-                        <TextBlock Margin="4">Zapisz</TextBlock>
-                    </Button>
+                    <TextBlock Style="{StaticResource Header}" VerticalAlignment="Center" DockPanel.Dock="Left">Cell Size</TextBlock>
+                    <Slider Minimum="8" Maximum="32" Value="{Binding Size}" VerticalAlignment="Center" />
                 </DockPanel>
             </StackPanel>
         </Grid>
diff --git a/Life/ViewModel/AutomatonViewModel.cs b/Life/ViewModel/AutomatonViewModel.cs
index 4cd47c9..cdfec2e 100644
--- a/Life/ViewModel/AutomatonViewModel.cs
+++ b/Life/ViewModel/AutomatonViewModel.cs
@@ -13,9 +13,23 @@ namespace Life.ViewModel
     {
         private int _size;
         private int _separation;
+        private int _width;
+        private int _height;
         private IAutomaton _automaton;
         private IFormatter _formatter = new BinaryFormatter();
 
+        public AutomatonViewModel()
+        {
+            PropertyChanged += (sender, args) =>
+            {
+                if (args.PropertyName == nameof(Field))
+                {
+                    Width = Field.Size.Width;
+                    Height = Field.Size.Height;
+                }
+            };
+        }
+
         public int Size
         {
             get => _size;
@@ -35,6 +49,26 @@ namespace Life.ViewModel
                 OnPropertyChanged(nameof(Separation));
             }
         }
+        
+        public int Width
+        {
+            get => _width;
+            set
+            {
+                _width = value;
+                OnPropertyChanged(nameof(Width));
+            }
+        }
+        
+        public int Height
+        {
+            get => _height;
+            set
+            {
+                _height = value;
+                OnPropertyChanged(nameof(Height));
+            }
+        }
 
         public IAutomaton Automaton
         {
@@ -54,6 +88,11 @@ namespace Life.ViewModel
         {
             Action = HandleCellClick
         };
+        
+        public ICommand ChangeSizeCommand => new DelegateCommand<object>
+        {
+            Action = HandleSizeChange
+        };
 
         public ICommand LoadCommand => new DelegateCommand<object>
         {
@@ -83,6 +122,12 @@ namespace Life.ViewModel
             Field.Notify();
         }
 
+        private void HandleSizeChange(object obj)
+        {
+            Field.Resize(Width, Height);
+            OnPropertyChanged(nameof(Field));
+        }
+
         private void HandleLoadCommand(object _)
         {
             OpenFileDialog dialog = new OpenFileDialog();
diff --git a/Life/ViewModel/FieldViewModel.cs b/Life/ViewModel/FieldViewModel.cs
index 6ee5bfe..62751ac 100644
--- a/Life/ViewModel/FieldViewModel.cs
+++ b/Life/ViewModel/FieldViewModel.cs
@@ -7,9 +7,11 @@ namespace Life.ViewModel
 {
     public class FieldViewModel : BaseViewModel
     {
+        private IField _field;
+
+        private Size _oldSize;
         private int _width;
         private int _height;
-        private IField _field;
         private int _size;
         private int _separation;
         private IDisposable _fieldObserverDisposal;
@@ -46,7 +48,8 @@ namespace Life.ViewModel
                 {
                     Action = field => Sync()
                 });
-                
+
+                _oldSize = value.Size;
                 _field = value;
                 ResetFields();
             }
@@ -107,6 +110,12 @@ namespace Life.ViewModel
 
         public void Sync()
         {
+            if (!Equals(_oldSize, Field.Size))
+            {
+                _oldSize = Field.Size;
+                ResetFields();
+            }
+            
             foreach (var cell in Cells)
             {
                 cell.IsAlive = Field[cell.Position.X, cell.Position.Y].IsAlive;