GIF Resizer — Change GIF Dimensions
Change animated GIF dimensions precisely with bilinear resampling. Keeping the aspect ratio locked guarantees your animation scales without stretching or distortion. Quick preset buttons let you target common responsive widths (480px, 320px, 240px, 128px) or generate standard 128×128 square custom emoji for Discord servers and Slack channels.
Use Cases
How to resize an animated GIF
Drop your animated GIF into the workspace. The initial dimensions, frame count, and file size appear instantly.
Enter custom width and height with aspect ratio lock enabled, or click a preset such as Discord Emoji 128×128.
Click Run to resample every frame using bilinear interpolation and re-encode the animation.
Review the output resolution and file size, then download the resized file or send it to another GIF tool.
Frequently Asked Questions
- Why should I lock the aspect ratio?
- Locking aspect ratio ensures that when you adjust width, height scales proportionally (and vice versa), preventing your animation from looking squished or stretched.
- What dimensions does Discord require for custom emoji?
- Discord requires custom emoji and stickers to be at least 128×128 pixels and under 256 KB. Using the 128×128 preset formats your GIF specifically for Discord.
- What resampling algorithm is used?
- Frames are resized using bilinear interpolation, which computes weighted averages of neighboring pixels for smooth gradients and clean edges without jagged artifacts.
- Does resizing reduce file size?
- Yes. Lowering resolution decreases the total number of pixels per frame, resulting in substantially smaller file sizes.
Private by design. Bilinear frame interpolation and GIF re-encoding run entirely in your browser — your GIF is never uploaded to a server.
Related tools
More free, in-browser tools from the GIF Tools set — every one runs locally, with no sign-up and no upload.