Question 1

Are my GIFs uploaded to your server?

Accepted Answer

No. All processing happens entirely in your browser via WebAssembly. Your GIFs never leave your device, which also means no file size limits and no privacy concerns.

Question 2

Is this compression lossless?

Accepted Answer

Yes. The current version uses gifsicle's lossless optimization (-O3), which re-encodes your GIF without dropping frames, palette colors, or resolution. The output looks pixel-for-pixel identical to the input. Typical savings range from 5% to 20% depending on how well your source was already encoded.

Question 3

How much can I expect to save?

Accepted Answer

For unoptimized GIFs (especially those exported from screen recorders or older tools), 10–20% savings are common. For GIFs that have already been compressed, savings will be smaller. If you need bigger reductions, future versions will add lossy controls (color palette reduction, frame skipping, resize) which can shrink files by 50% or more.

Question 4

What is the largest GIF I can compress?

Accepted Answer

There is no enforced limit, but very large GIFs (above ~25 MB) may take several seconds and use significant memory in your browser. Performance depends on your device. If a large GIF fails to process, try restarting your browser tab to free memory.

Question 5

What is gifsicle?

Accepted Answer

Gifsicle is the standard open-source GIF manipulation tool, originally written by Eddie Kohler. It has been the go-to GIF optimizer for over two decades. This tool runs a WebAssembly build of gifsicle 1.92 directly in your browser, so you get the same output as the command-line version without installing anything.

GIF Minifier