How to resize an image to 640x640
- Choose or drop your images above.
- Keep “Crop to fill” for an exact 640x640 result, or pick “Fit inside” to avoid cropping.
- Download the resized files individually or as a ZIP.
About 640x640 pixels
A 640x640 image is square, with an aspect ratio of 1:1, and holds 0.41 megapixels. At 300 DPI it would print at about 2.1 x 2.1 inches (5.4 x 5.4 cm). As a JPEG it usually lands between 45KB and 90KB, depending on the picture and the quality you choose.
Where 640x640 is used
A mid-sized square used for blog pictures, avatars and some marketplace fields.
- A square crop keeps the centre of the photo, so frame the subject in the middle.
- Start from the largest original you have. Enlarging a small picture makes it look soft.
- Use JPG for photos and PNG for graphics with text or transparency.
Crop to fill or fit inside?
Crop to fill always gives exactly 640x640 by trimming the edges that do not match the shape. Fit inside keeps the whole picture and scales it so neither side exceeds 640x640, which can leave one side shorter. For a typical 4:3 phone photo, crop to fill removes about 25% of the picture. A 3:2 camera photo loses about 33%, a 16:9 screenshot about 44%, and a square image about 0%.
Quality and format
Check the result before you upload
Open the finished file and check three things: the picture measures 640x640, the subject is not cut off, and the file is small enough for where you upload it. If a platform sets a size limit, run the result through the online compression tool or choose a limit such as 200KB.
A tip for this size
Compress the result if the page needs to load fast on phones. Need another size? Try 600x600, 512x512, 800x800, the general image resizer, or browse every size preset.
Frequently asked questions
Why is my image not exactly 640x640?
You are probably using Fit inside, which never crops. Switch to Crop to fill for exact dimensions.
How big will a 640x640 file be?
As a JPEG, usually between 45KB and 90KB. Photos with lots of fine detail come out larger, and simple graphics smaller. Lower the quality for a smaller file.
Is 640x640 the right size for square web images?
It is a widely used size for square web images, but platforms and agencies change their rules. Check the current guidelines before you upload.
Will detail survive at 640x640?
At small sizes fine detail disappears. Crop in close on the main subject and use a simple, high-contrast picture for the best result.