Slack emoji resizer
Shrink an animated GIF or image into a square Slack emoji under 128 KB. The animation is kept.
How to resize an emoji for Slack
- Drop an animated GIF, PNG, JPG, or WebP into the box above.
- Pick the size (128 px is the usual one) and whether to fit the whole image or crop it to a square.
- The tool resizes every frame and re-encodes the GIF until it is under 128 KB. The checklist shows the size, frame count, and file size.
- Download the file. In Slack, open the emoji picker in any message box and choose Add emoji, or go to your workspace name, then Customize workspace. Upload the file and paste the name the tool suggests.
Frequently asked questions
What size should a Slack emoji be?
Slack's help center asks for square images under 128 KB, in JPG, PNG, or GIF format. 128x128 pixels is the usual size. Emoji show at 32 pixels or smaller in messages, so a bigger image looks the same and only adds file size.
What is the Slack emoji GIF size limit?
The same 128 KB as any emoji, and Slack's help center says a GIF can have up to 50 frames. This tool checks both and shows the result before you download.
How do I resize a GIF for Slack without losing the animation?
Drop it in the resizer above. It decodes every frame, scales each one to the size you pick, and writes a new animated GIF. If the source has more than 50 frames, it keeps 50 spread across the clip and adds the skipped frames' time to their neighbors, so one loop lasts as long as before.
How does the tool get a GIF under 128 KB?
It tries the cheapest cut first. It lowers the color count, then the pixel size, and then keeps every second frame. In clips without transparency, frames after the first only store the pixels that changed, which cut a test clip from 281 KB to 185 KB. The result line shows which settings it used.
Why does Slack say my emoji file is too big?
The file is over 128 KB. Phone photos and screen recordings often run to several megabytes, so resize them first. A 128x128 PNG is almost always under the limit. Long or noisy GIFs are the ones that need fewer colors or a smaller size.
Is this Slack emoji resizer free, and is my file uploaded?
It is free with no account or watermark. Decoding, resizing, and encoding run in your browser, so the file never leaves your computer.
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