When this tool is useful
Removing a fixed border, caption strip, browser chrome, or unused canvas area that stays in the same location throughout a GIF.
How local processing works
The browser composes source frames using GIF disposal rules, validates one crop against the logical screen, copies that rectangle from every visible RGBA frame, and re-quantizes the outputs with parsed delays and loop behavior.
How to use it
- Prepare the source and limits: Keep an unchanged source and review the accepted format, dimensions, frame or page budget, and output choices. Removing a fixed border, caption strip, browser chrome, or unused canvas area that stays in the same location throughout a GIF.
- Process locally: Run the documented bounded operation in this browser and stop when the decoder reports an unsupported structure. The browser composes source frames using GIF disposal rules, validates one crop against the logical screen, copies that rectangle from every visible RGBA frame, and re-quantizes the outputs with parsed delays and loop behavior.
- Download and verify: Scrub or play the entire result, not only its first frame, confirm no later motion crosses the crop boundary, compare timing and loop count, and inspect transparent edges and palette changes on contrasting backgrounds.
Important limitations
A single fixed rectangle is used for all frames; it does not track moving subjects or choose content-aware crops. Re-encoding is lossy because GIF palettes, dithering and binary transparency are rebuilt, delays are limited to centiseconds, and a crop can permanently remove motion entering the excluded area.
Verify the downloaded result
Scrub or play the entire result, not only its first frame, confirm no later motion crosses the crop boundary, compare timing and loop count, and inspect transparent edges and palette changes on contrasting backgrounds.
Private by design
Your files stay in this browser. The tool does not upload the source or output to our servers.
Questions and answers
When is this workflow useful?
Removing a fixed border, caption strip, browser chrome, or unused canvas area that stays in the same location throughout a GIF.
What does local processing do?
The browser composes source frames using GIF disposal rules, validates one crop against the logical screen, copies that rectangle from every visible RGBA frame, and re-quantizes the outputs with parsed delays and loop behavior.
Which format limits matter?
A single fixed rectangle is used for all frames; it does not track moving subjects or choose content-aware crops. Re-encoding is lossy because GIF palettes, dithering and binary transparency are rebuilt, delays are limited to centiseconds, and a crop can permanently remove motion entering the excluded area.
How should I verify the download?
Scrub or play the entire result, not only its first frame, confirm no later motion crosses the crop boundary, compare timing and loop count, and inspect transparent edges and palette changes on contrasting backgrounds.