Frames, not a first frame
Many resizers open an animated GIF as a picture and quietly keep only the first frame. Here the file is read frame by frame: each frame is composited the way a browser shows it (transparent pixels, frames that only redraw part of the picture, frames that restore what was underneath), resized through the same scaler as a photo, and written back with its delay.
A rule that asks for JPEG, PNG or WebP still writes an animated source as a GIF, and the plan row says so before anything runs, because no frame should be lost to a format setting.
Sizes that suit GIFs
Quick buttons set the common widths: 480 for chat and forums, 320 for small embeds, and half size. Width is what matters most for weight, because a GIF stores every pixel of every frame.
Questions about gIF resizer
Does the animation survive?
Yes. Each frame is drawn onto the full picture the way a viewer shows it, resized, and written back with its own delay. The loop count is copied. An animated GIF is never flattened to its first frame.
Why does my GIF look a little different?
A GIF holds at most 256 colours per frame. Resizing blends neighbouring pixels into new colours, so each frame gets a fresh palette of up to 256 picked from the resized frame. Smooth gradients can band slightly.
Can it make the GIF smaller in KB?
Making it narrower is what shrinks a GIF most: half the width is roughly a quarter of the pixels. The KB limit field is for JPEG, PNG, WebP and AVIF; it is not applied to animated GIFs.
What about animated WebP?
Animated WebP is not decoded here, so it is listed as skipped rather than turned into a still. Animated GIF is.
Is the GIF uploaded?
No. The GIF is decoded, resized and encoded by this page on your device; there is no server that receives it.
