Question 1

What is 256x256 used for?

Accepted Answer

256×256 is the Avatar size, used for profile pictures and avatars. Matching it exactly avoids the platform cropping or re-compressing your image in a way you did not choose.

Question 2

How do I resize an image to 256x256 without stretching it?

Accepted Answer

Crop to the right shape first, then scale. Scaling a differently-proportioned image straight to 256×256 distorts it; cropping to 1.00:1 first and then scaling keeps everything in proportion.

Resize to 256 × 256