GIF Optimizer
Make animated GIFs smaller while they keep their size, frame rate and length. The optimizer rebuilds the colour palette from the whole animation, lets you choose how gradients are dithered, and stores only the part of each frame that actually changes, which is where most GIFs waste space. It runs FFmpeg in your browser and keeps the original if it cannot be improved.
- Files stay on your device
- No sign-up
- Free to use
How to use GIF Optimizer
- Drop one or more animated GIFs onto the page.
- Choose the number of colours and dithering.
- Keep “store only the changed area” on for the biggest saving.
- Optimize and download.
GIF Optimizer features
Same animation
Size, speed and frames unchanged.
Optimized palette
Built from all frames together.
Changed-area frames
Unchanged pixels compress away.
Dithering choice
Ordered, error diffusion or none.
Never larger
Original kept if already optimal.
Private
Converted in your browser; nothing is uploaded.
When to use GIF Optimizer
- Lighter GIFs for chats, forums and e-mails.
- Faster documentation and README animations.
- Reducing GIFs exported from screen recorders.
- Meeting upload limits without resizing.
GIF Optimizer FAQ
How is this different from the GIF Compressor?
The optimizer keeps everything about the animation and only encodes it better. The GIF Compressor can also make it smaller by reducing dimensions, frame rate or length.
Why can storing changed areas save so much?
In screen recordings and many animations, most pixels stay the same from frame to frame. Storing only the rectangle that changes, with transparent pixels elsewhere, lets compression remove the repeated data.
Which dithering should I choose?
Ordered dithering compresses best and suits most content; error diffusion looks smoothest on photos; none is best for flat graphics.
Why is FFmpeg so large?
The WebAssembly build of FFmpeg (about 32 MB) is downloaded once and cached; it is the same engine used by professional video tools.
Are my files uploaded?
No. Everything happens in your browser.
Where GIF files waste space
GIF is an old format with tight limits: at most 256 colours per frame and simple LZW compression. Animations are stored as a sequence of frames, and many GIF creators write every frame in full with a palette chosen frame by frame. The result is large files that are much bigger than they need to be.
The optimizer re-encodes the animation with FFmpeg in two steps. First, palettegen analyses all frames and builds one palette of up to 256 colours that represents the whole animation well. With the changed-area option, it gives priority to colours in the moving parts, which matter most to the eye.
Second, paletteuse maps every frame to that palette with the dithering you choose. In rectangle diff mode, only the area that differs from the previous frame is written; everything else is transparent and compresses almost to nothing. For screen recordings, animated diagrams and UI demos, this alone often halves the file.
Fewer colours make files smaller again, at the cost of smoother gradients. For a GIF that has to be much smaller, reduce the dimensions or frame rate with the GIF Compressor.
For new projects, consider whether an animation needs to be a GIF at all: a short MP4 or WebM video is usually many times smaller and plays smoothly on every platform that allows video.
FFmpeg runs as WebAssembly in your browser, so your GIFs stay on your device.