If you need to prepare a product image for Walmart or another retailer that requires a square format, Photopea is a simple free tool that can handle it directly in your browser. No account is required. This guide shows how to turn a rectangular image into a 1:1 square, fill the expanded canvas with white, and export it at the required pixel size.
Photopea: https://www.photopea.com/
Step-by-Step Instructions
Step 1: Open Photopea
Go to Photopea.com.
Step 2: Add your image
Drag your image into the work area. Once it opens, you are ready to adjust the canvas.
Step 3: Open Canvas Size
In the Image menu, click Canvas Size.
Shortcut: Shift + Option + Command + C
Step 4: Make the canvas square
Change the Height value so it matches the Width value. In this example, the width is 2310 px, so enter 2310 px for the height as well.
Step 5: Confirm the 1:1 aspect ratio
Once the width and height match, the aspect ratio will change to 1:1. Your image is now set to a square canvas.
Step 6: Keep the image centered
Use the anchor point control to tell the software where to place the existing image inside the new square canvas. For this image, leave it centered.
Step 7: Apply the new canvas size
Click OK.
The canvas will expand into a square. You will notice that the new space at the top and bottom is transparent.
Step 8: Create a new layer
To turn the transparent area white, create a new layer.
You can do this by clicking the New Layer icon at the bottom of the Layers panel, or by going to Layer > New > Layer.
Step 9: Move the new layer underneath the image
The new layer will be transparent by default. In the Layers panel, drag it below your Background layer so it sits at the bottom.
Step 10: Set your color to white
Make sure your selected color is white before filling the new layer.
Step 11: Select the Paint Bucket tool
In the toolbar, choose the Paint Bucket Tool.
Note: This tool is nested under the Gradient Tool. Click and hold the Gradient Tool to reveal it.
Step 12: Fill the background with white
With the new layer selected and white as your active color, click anywhere on the image.
The new bottom layer will fill with white, matching the original background.
Step 13: Export the image
Go to File > Export As > PNG or JPG.
Step 14: Set the final output size
During export, enter the required output dimensions, such as 1500 x 1500 px or 2200 x 2200 px.
Step 15: Save the file
Choose your save location and export the final image.
Final Result
You now have a square product image with a clean white background, ready for retailer upload requirements.