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Resize GIF

In your browser, no upload

GIF

75% · 50% · 25% or a width · timing kept

GIF

Smaller or larger, timing kept

Specification

7 rows
Resize GIF specification
ItemValueNotes
InputGIFStill or animated
OutputGIFThe same number of frames
Size75% · 50% · 25%, or a widthAspect kept, up to 2× the original width
Colours256 per frameScaling blends colours, so frames are reduced again
TransparencyKept, on or offA soft edge is decided at the halfway point
TimingAs storedEvery frame’s delay and the loop count
Processed inThis browserNot sent to a server

What happens

3
What happens, and why

Drop a GIF and pick a size: 75% · 50% · 25% of the original width, or a width in pixels. The height follows, so the picture is never stretched. Every frame is put back together the way a browser shows it, drawn at the new size and written into a new GIF with the same number of frames, the same delays and the same loop count. It happens inside this browser; the GIF is not sent to a server.

Scaling is a re-encode, and the badge says so. Drawing a picture at another size blends neighbouring pixels into colours the file did not have, and a GIF frame holds at most 256, so each frame is reduced to 256 colours again. GIF also has no partial transparency: the soft edge a scaler draws around a transparent part becomes opaque or transparent at the halfway point.

To keep the file small, a frame of an opaque animation stores only the rectangle that changed since the frame before, which is how GIF tools write animations. An animation with transparent parts is written as whole frames, because a later frame could not make a pixel transparent again otherwise. Typing the original width redraws nothing: when every frame then fits 256 colours, the pixels are the source’s and the badge says no quality was lost.

FAQ

3
How do I make a GIF smaller in file size

Fewer pixels is the surest way: half the width is a quarter of the pixels. The size of the new file is shown next to the result, with the original’s.

Can I make it an exact size, like 128 × 128

Type the width; the height follows the original’s proportions, so a square GIF becomes 128 × 128. To change the proportions, crop it first: the crop tool cuts GIFs without re-encoding, animation and timing kept.

Why does the resized GIF look grainier

Each frame is limited to 256 colours. Scaling mixes colours, and fitting them back into 256 can show as banding or speckle in gradients. Pixel art and flat colours come through cleanly; photographs show it most.

Related specs

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