GIF Speed Changer
Speed up, slow down or reverse an animated GIF by re-timing every frame.
Re-time an Animated GIF
A GIF stores a delay with every frame, measured in hundredths of a second. Changing the speed of an animation means rewriting those delays — which requires decoding the file, reading every frame, and encoding a new one.
This tool does exactly that, with a GIF decoder and encoder written for this project. It also handles the format’s awkward edges: delays below 0.02 s that browsers silently clamp, frame disposal methods that decide what each frame is drawn over, and transparency that has to survive the round trip.
Key features
- 0.25× to 5× speed — with presets for the common cases and a live readout of the new duration.
- Reverse playback — flip the frame order as well as the timing.
- Proper decoding — frames are fully composited, honouring disposal methods and transparency, before being re-encoded.
- Palette control — choose the colour count for the re-encode to trade quality against file size.
- Preview the result — the new GIF plays in the page before you decide to keep it.
This tool runs entirely inside your browser using native Web APIs. Your files and text are never uploaded to a server, never logged and never shared with third parties.
How to use: GIF Speed Changer
- Drop in the GIF
It is decoded in the page and the frame count and original duration appear. - Set the speed
Drag the slider or use a preset. The new total duration is shown as you adjust. - Reverse it if you like
Tick the box to play the frames backwards as well. - Save the re-timed GIF
The animation is re-encoded and downloaded, and previewed so you can check it.
Technical specifications
| Processing location | Entirely in your browser — no server round trip |
|---|---|
| Data uploaded | None. Files and text never leave your device |
| Price | Free — no account, no trial, no usage cap |
| Category | Media |
| Works offline | Yes, once the page has loaded |
| Browser support | Chrome 90+, Edge 90+, Firefox 90+, Safari 15+ |
| Interface languages | English, 中文, हिन्दी, Español, العربية |
Frequently asked questions
Why can I not make a GIF infinitely fast?
The format stores delays in hundredths of a second and browsers clamp anything under about 0.02 s to a slower default. Past that point, speeding up means dropping frames rather than shortening delays.
Will re-encoding lose quality?
Slightly, because the frames are re-quantised to a new palette. Setting the colour count to 256 keeps the loss negligible for most animations. The frames themselves are decoded exactly.
Does it keep transparency?
Frames are composited during decoding, which resolves transparency and disposal correctly. The output is opaque, which is what makes the timing predictable across viewers.
Is there a size limit?
No fixed limit, but long or large GIFs hold every frame in memory as full RGBA. A 500×500 GIF with 200 frames is 200 MB decoded, which is fine on a desktop and heavy on a phone.