Free Online GIF Image Compression
GIFs that open instantly, animation still smooth
ImageTool.app's online GIF compressor reduces GIF file size while keeping animations smooth. Everything runs locally — no upload required.
![](data:image/svg+xml,%3c?xml%20version='1.0'%20encoding='UTF-8'?%3e%3csvg%20width='107px'%20height='93px'%20viewBox='0%200%20107%2093'%20version='1.1'%20xmlns='http://www.w3.org/2000/svg'%20xmlns:xlink='http://www.w3.org/1999/xlink'%3e%3ctitle%3e形状%3c/title%3e%3cg%20id='页面-1'%20stroke='none'%20stroke-width='1'%20fill='none'%20fill-rule='evenodd'%3e%3cg%20id='iMac-21.5"'%20transform='translate(-907,%20-462)'%20fill='%23818198'%20fill-rule='nonzero'%3e%3cg%20id='logo'%20transform='translate(907,%20462)'%3e%3cpath%20d='M95.1111111,0%20L11.8888889,0%20C5.35,0%200,4.62627551%200,10.3201531%20L0,82.6798469%20C0,88.3737245%205.35,93%2011.8888889,93%20L95.1111111,93%20C101.65,93%20107,88.3737245%20107,82.6798469%20L107,10.3201531%20C107,4.62627551%20101.65,0%2095.1111111,0%20Z%20M101.055556,81.9681122%20C101.055556,84.815051%2098.3805556,87.0688776%2095.1111111,87.0688776%20L11.8888889,87.0688776%20C8.61944444,87.0688776%205.94444444,84.7557398%205.94444444,81.9681122%20L5.94444444,48.3979592%20L29.96,64.2933673%20C34.9533333,67.5554847%2041.7894444,67.8520408%2047.0205556,64.8864796%20L59.5633333,57.9470663%20C62.2977778,56.4049745%2065.8644444,56.286352%2068.7177778,57.7098214%20L101.055556,73.190051%20L101.055556,81.9681122%20Z%20M101.055556,65.4795918%20L71.6305556,52.0752551%20C66.875,49.8807398%2060.99,49.9993622%2056.3533333,52.4904337%20L43.8105556,59.1332908%20C40.66,60.7940051%2036.5583333,60.6753827%2033.5861111,58.7774235%20L5.94444444,41.2806122%20L5.94444444,11.091199%20C5.94444444,8.42219388%208.61944444,6.22767857%2011.8888889,6.22767857%20L95.1111111,6.22767857%20C98.3805556,6.22767857%20101.055556,8.42219388%20101.055556,11.091199%20L101.055556,65.4795918%20Z'%20id='形状'%3e%3c/path%3e%3c/g%3e%3c/g%3e%3c/g%3e%3c/svg%3e)
Drop image files here to compress online, losslessly
A 5-second UI demo or a social reaction GIF can easily be 8–15MB — too big for email, Slack or web embeds. ImgZilla compresses GIFs with frame differencing, palette reduction and lossless animation optimization, entirely locally, no upload.
How we compress GIF
Frame differencing
Stores only what changes between frames rather than each full frame, cutting size dramatically for static backgrounds or slow motion.
Palette optimization
Perceptual color selection picks the 256 colors the eye is most sensitive to, trimming the palette with no visible banding.
Dither control
From Floyd–Steinberg dithering for gradients to no dithering for flat-color animations — pick what fits.
Batch processing
The desktop app compresses an entire GIF library at once — email campaigns, product docs, social assets — in seconds.
How to compress GIF
Drop in a GIF
Just drag your animated GIF in — no upload.
Export the GIF
Same duration and frame count, noticeably smaller file.
FAQ
Every frame is a full image with its own palette. A 3-second, 15fps animation is 45 frames — size adds up fast without optimization.
No. Optimization only targets data redundancy and color efficiency; duration, frame count and look are all preserved.
Yes. A GIF's binary transparency is fully preserved throughout compression.
Download ImgZilla for faster batch compression
Want faster batch compression and stronger privacy? The ImgZilla desktop app does everything locally on your Mac — just drag and drop.
- 100% local processing — images are never uploaded
- Multi-threaded batch compression, up to 90% smaller
- Originals auto-backed up to Trash, recoverable anytime
- Compare before and after with the built-in image compare tool