How to View Images Side by Side in Paint.NET

This article explains how to view and work on multiple images side by side in Paint.NET. Because Paint.NET uses a single-window tabbed interface rather than a traditional Multiple Document Interface (MDI), native cascading or tiling of internal document windows is not supported. Below, you will find straightforward workarounds to place images side by side on a single canvas for simultaneous editing or view them concurrently using Windows system features.

Understanding Paint.NET's Window Limitation

Paint.NET manages all open files as thumbnail tabs across the top-right corner of the interface. It does not allow users to tear off tabs into separate windows, nor does it provide a native "Tile" or "Cascade" command. To achieve a side-by-side workspace, you must either expand the working canvas to hold both images or use an external viewer alongside Paint.NET.

Combining two images into one document allows you to edit, compare, and sample colors from both files side by side.

  1. Open both images in Paint.NET. They will appear as separate thumbnail tabs at the top of the screen.
  2. Note the dimensions of the images by clicking Image > Canvas Size on each image.
  3. Switch to your primary image.
  4. Click Image > Canvas Size (or press Ctrl + Shift + R).
  5. In the dialog:
    • Maintain the existing Height (or adjust it to match the taller image).
    • Double the Width (e.g., if the width is 800 pixels, change it to 1600 pixels).
    • Under the Anchor section, select the Left middle arrow so the original image stays on the left side.
    • Click OK.
  6. Switch to the second image via the top thumbnail bar.
  7. Press Ctrl + A to select all, then Ctrl + C to copy the image.
  8. Switch back to the expanded canvas.
  9. Click Layers > Add New Layer (or press Ctrl + Shift + N).
  10. Press Ctrl + V to paste the image.
  11. Use the Move Selected Pixels tool (blue arrow icon) to drag the pasted image into the empty space on the right side.

Method 2: Compare Images Using Layer Overlays

If the purpose of tiling is alignment or direct comparison, layering is faster than resizing:

  1. Open your base image.
  2. Go to the second image, press Ctrl + A, and press Ctrl + C.
  3. Return to the base image and press Ctrl + Shift + V to paste it into a new layer automatically.
  4. Open the Layers panel (F7).
  5. Double-click the top layer to adjust its Opacity or toggle the checkbox next to the layer to quickly switch back and forth between the two views.

Method 3: Side-by-Side Viewing with Windows Snap

If you only need the second image as a reference while editing in Paint.NET, use the Windows desktop tiling feature:

  1. Open the image you want to edit inside Paint.NET.
  2. Open the reference image using the default Windows Photos app or another lightweight image viewer.
  3. Select the Paint.NET window and press Windows Key + Left Arrow to snap it to the left half of your screen.
  4. Select the image viewer window and press Windows Key + Right Arrow to snap it to the right half.