Bluesky's image size limit has been increased to 4000 x 4000 pixels.

Bluesky version 1.121 was released on April 23, 2026, Japan time. The maximum resolution for uploaded images has been increased to 4000 x 4000 pixels, and the display format for posts containing multiple images has been changed.

This update expands the maximum image resolution for uploads to Bluesky to 4000 x 4000 pixels and the maximum file size to 2MB. To test this, I'll upload a photo taken with an iPhone with a resolution of 2268 x 4032 pixels and a file size of 3.1MB.

The posting process remains the same.

The results of the submissions are as follows:

Upon downloading the image from Bluesky and checking its details, I found that the resolution had been reduced to '2250 x 4000 pixels' and the file size to '1.4MB'.

Version 1.121 also includes a change to the display format for posts containing multiple images, which now show images side-by-side within the post. You can quickly browse through the images in the post by swiping left or right on the image area.