GIF Optimizer

What GIF Optimizer does

GIF Optimizer cuts the file size of an animated GIF and leaves its width and height alone. To change dimensions, use GIF Resizer; to swap the GIF for an MP4 video, use GIF To Video.

It saves bytes in two ways. It drops frames down to the frame rate you pick, and it rebuilds the animation around a smaller shared color palette. Fewer frames and fewer colors each leave less data to store.

How to use it

1. Select Choose File and load the GIF to shrink. A first optimized copy renders straight away using the default settings.
2. Adjust Frame Rate (fps) and drag the Compression slider. Every change triggers a fresh render after a short pause, so there is no separate optimize button.
3. Compare Input Preview with Output Preview. Both animations restart together after each render, and the Original size and Output size lines show how much you saved.
4. Select Download GIF to save the smaller file.

Formats and limits

• Input: GIF files only. The file picker is filtered to .gif.
• Output: a GIF named after the original with -optimized appended, so party.gif becomes party-optimized.gif.
• Frame dimensions match the source; only timing and colors change.
• The tool sets no size cap, but long or high-resolution animations take noticeably longer, because the engine runs on a single thread inside the page.

Settings explained

Frame Rate (fps)

How many frames are kept per second, 15 by default and never below 1. Lower numbers remove frames for a lighter but choppier result. A value above the GIF's own rate cannot add smoothness that was never there.

Compression

Ranges from 0 to 100%, starting at 35%. It limits the new palette to 256 colors at 0%, stepping down evenly to 32 colors at 100%. The caption reads Light compression below 30%, Balanced compression up to 69%, and Aggressive compression from 70%.

Advanced logs

Adds a line to the Status log at every 10% of progress, which helps you tell a slow render from a stalled one.

Further reading

• Make a GIF smaller - Cut unnecessary frames, reduce dimensions, and compare motion and colors before sending a GIF.

Privacy

Optimization happens inside this browser tab. A WebAssembly build of FFmpeg is fetched from the jsDelivr CDN on the first render, or from this website if the CDN cannot be reached, and your animation is read into page memory and never sent to a server. Selecting Clear removes both previews from the page.

FAQ

Why is the optimized GIF barely smaller?

A GIF that already uses few colors or frames has little left to trim. Lower Frame Rate first, since each dropped frame removes a whole picture, then push Compression higher.

What is the fine dot pattern in my output?

That is dithering. The optimizer mixes the reduced palette in a regular pattern to imitate missing shades, and it shows most on smooth gradients at high Compression. Lower Compression to soften it.

Does a lower frame rate shorten the animation?

No. Frames are removed or repeated to reach the new rate, but the overall timing is kept, so the loop lasts as long as before.

Which colors does the new palette keep?

The palette is chosen with extra weight on the parts of the picture that change between frames, so moving subjects keep their colors better than a still background.

Related tools

• GIF Resizer - make the frames smaller in pixels.
• GIF Inspector - see the frame rate and palettes before choosing settings.
• GIF Frame Editor - delete, reorder, or retime frames before optimizing.
• Animated Image Converter - save as an animated WebP, which is often smaller.
• GIF To Video - switch to an MP4 when the destination accepts video.