Crop Images to Aspect Ratios in Paint.NET

Cropping an image to a specific aspect ratio in Paint.NET is a straightforward process achieved by configuring the Rectangle Select tool. By switching the tool's selection mode from standard freeform to a fixed ratio, you can lock your selection box to dimensions like 16:9, 4:3, or 1:1 before trimming the canvas. This guide walks you through the exact steps to select your desired ratio and crop your image cleanly.

Step 1: Open Your Image

Launch Paint.NET and open the image you want to edit by going to File > Open or pressing Ctrl + O.

Step 2: Choose the Rectangle Select Tool

Select the Rectangle Select tool from the Tools palette on the left side of the screen, or simply press the S key on your keyboard until the rectangular icon is active.

Step 3: Set the Selection Mode to Fixed Ratio

Look at the tool settings bar across the top of the canvas:

  1. Locate the dropdown menu labeled Normal.
  2. Click the dropdown and select Fixed Ratio.
  3. Two input boxes labeled Width and Height will appear to the right of the dropdown.

Step 4: Enter Your Desired Aspect Ratio

Type your target ratio values into the Width and Height fields:

  • For widescreen displays or standard video thumbnails, enter 16 in Width and 9 in Height.
  • For traditional photography, enter 3 in Width and 2 in Height (or 2 and 3 for portrait).
  • For square formats (such as profile pictures), enter 1 in Width and 1 in Height.

Step 5: Draw and Adjust the Selection

  1. Click and drag across your image. The selection box will automatically maintain the exact aspect ratio you defined.
  2. If you need to reposition the selection box without altering its size or shape, switch to the Move Selection tool (white arrow icon) in the Tools palette or press M. Click and drag inside the selected area to slide it over the subject.

Step 6: Crop to the Selection

Once the bounding box covers the exact portion of the image you want to keep, execute the crop:

  • Go to the top menu and select Image > Crop to Selection.
  • Alternatively, press the keyboard shortcut Ctrl + Shift + X.

Step 7: Save Your Cropped Image

Go to File > Save As to save your cropped image as a new file, preserving the original uncropped source.