Why this is the fastest GIF compressor on the web
Two-pass palette compression (what makes a compressed GIF actually look right) is heavy: palettegen across the whole clip, then paletteuse with Bayer dithering per frame. Browser ffmpeg.wasm tools do this single-threaded with a ~2 GB memory cap and routinely crash on big GIFs. We rebuilt the pipeline: presigned upload to the nearest Backblaze B2 POP, native ffmpeg on our server, output delivered through Bunny CDN. A 10 MB GIF typically shrinks to 2–4 MB in 4–8 seconds.
Why GIFs are so much bigger than they should be
A GIF stores every frame as its own full image. There is no inter-frame compression — no concept of "this pixel is the same as the last frame, so skip it," which is the entire trick that makes MP4 and WebM tiny. So a three-second screen capture that would be a 300 KB MP4 routinely balloons to 8–15 MB as a GIF. The format dates to 1987 and was never designed for the high-resolution, high-frame-rate clips people make today. That is also why the two levers on this page matter so much: shrinking the width cuts the pixels-per-frame, and capping the colour palette cuts the bytes-per-pixel.
Settings that actually move the needle
Start by lowering the width. Most GIFs are viewed in a chat sidebar or an inline comment at a fraction of their native size, so a 960 px GIF squeezed down to 480 px looks identical and is roughly a quarter of the file. Next, drop the colour count. A screen recording with flat UI colours looks perfect at 64 colours; a colourful photo-real animation may need 128–256. This tool also caps the frame rate at 12 fps, which is plenty for screen content. If the result still is not small enough, push the width down before sacrificing colours.
Targets for Slack, Discord, and email
Discord caps uploads at 10 MB on the free tier, Gmail rejects attachments over 25 MB, and Slack will technically take more but throttles the inline preview on anything large. For all three, aim for the 2–6 MB range and your GIF will both upload and animate inline without nagging.
For big animations, share a video link instead
There is a ceiling to GIF compression. Past a few seconds, no amount of palette-trimming beats simply not using GIF. A 20-second walkthrough that is a stubborn 14 MB GIF is a 500 KB MP4 — and every modern chat app, doc tool, and email client now plays MP4 inline. If you are compressing a GIF to squeeze a product demo under an upload limit, the better move is to record it with Clipy and paste a hosted video link, or convert your GIF using GIF to MP4 converter.
Sister tools
Already at the MP4 stage? Video compressor shrinks H.264 for Slack, Discord, X, and email caps. Need to make a GIF from a video? MP4 to GIF converter and Video to GIF converter use the same two-pass palette pipeline. Trim or resize first? Trim video and Resize video handle the prep steps.