1:1 aspect ratio
1:1 is the square shape: 1 units wide for every 1 tall, which is 1 as a decimal. 640 x 640 px is 1:1 because 640 divided by 640 gives 1, and the fraction reduces to 1:1. 14 of the image sizes on this site use it.
Where 1:1 comes from
The square is the shape of an avatar. It is the only ratio that survives being displayed as a circle without anyone having to decide which side to cut, which is why profile pictures use it almost everywhere. It was also Instagram's original and only feed shape.
Which platforms use 1:1
Read live from the specification data, so this list changes when a platform does. Last verified 2026-07-27.
| Platform | Asset | Size (px) | Source |
|---|---|---|---|
| Profile picture | 640 x 640 | Convention | |
| YouTube | Profile picture | 800 x 800 | Documented |
| Profile picture | 320 x 320 | Documented | |
| Post image | 1200 x 1200 | Convention | |
| Company Page logo | 400 x 400 | Documented | |
| Profile picture | 400 x 400 | Convention | |
| X (Twitter) | Profile picture | 400 x 400 | Convention |
| TikTok | Profile picture | 400 x 400 | Convention |
| Discord | Profile picture (avatar) | 512 x 512 | Convention |
| Twitch | Profile picture | 256 x 256 | Convention |
| Threads | Profile picture | 640 x 640 | Convention |
| Telegram | Channel photo | 512 x 512 | Convention |
| Avatar | 256 x 256 | Convention | |
| Bluesky | Avatar | 1000 x 1000 | Convention |
1:1 in pixels
Every row below is calculated from the ratio rather than looked up, so the heights are exact where the arithmetic is exact and rounded to the nearest whole pixel where it is not. A fractional pixel is not something a file can store.
| Width | Height | Used by |
|---|---|---|
| 256 px | 256 px | Twitch profile picture, Reddit avatar |
| 320 px | 320 px | Facebook profile picture |
| 400 px | 400 px | LinkedIn company page logo, LinkedIn profile picture, X (Twitter) profile picture, TikTok profile picture |
| 512 px | 512 px | Discord profile picture (avatar), Telegram channel photo |
| 640 px | 640 px | Instagram profile picture, Threads profile picture |
| 800 px | 800 px | YouTube profile picture |
| 1000 px | 1000 px | Bluesky avatar |
| 1200 px | 1200 px | LinkedIn post image |
Cropping and letterboxing into 1:1
Square is the safest shape to hand to a surface you do not control. If a platform crops it, it crops symmetrically, and if it masks it into a circle, the corners are the only thing at risk.
There are only two honest ways to put an image of one shape into a frame of another. Crop to fill keeps the frame full and throws away whatever does not fit, which is almost always what you want for a feed. Fit inside keeps the whole image and pads the remaining space, which is what you want when the image is a diagram, a screenshot or anything where losing an edge loses meaning. Scaling to fit without doing either, so the image is stretched, is the one option that is always wrong.
Work out a 1:1 size
Enter a width or a height and the calculator solves the other side. It runs in your browser and nothing is uploaded.
Other ratios
See the aspect ratio guide for the shapes side by side, or the full cheat sheet for every size on one page.