The three levers, and what each costs
Dimensions give the biggest return and the most honest trade: halving the width removes three quarters of the pixels and the animation is unchanged, just smaller on screen.
Frames come next. Dropping every second frame halves the file and makes the motion slightly steppier — usually invisible on a screen recording, obvious on fast camera movement.
Colours are last. Going from 256 to 64 saves less than you might expect and shows first on gradients and skin tones. On a flat-coloured graphic it is nearly free.
Why the saving is smaller than for a photo
A JPG compressor can throw away detail the eye ignores. GIF is already indexed to a small palette and compressed losslessly on top, so there is much less slack. Do not expect the 80% reductions ordinary image compression gets.
If the target is a hard size limit — an email attachment cap, a forum’s upload rule — dimensions are the lever that will actually get you there.
The bigger question
A long GIF is the wrong format rather than a badly compressed one. Converting to MP4 with GIF to MP4 routinely gives a tenth of the size at better quality. Compress the GIF when it has to stay a GIF; convert it when it does not.
Frequently asked questions
How much smaller can a GIF get?
Typically 30–70%, depending mostly on how far you reduce the dimensions and frames. Photographic GIFs compress worst because they were already struggling inside a 256-colour palette.
Which setting should I change first?
Dimensions, then frame count, then colours. That is the order of effect on size and the reverse order of how visible the damage is.
Will it still animate?
Yes — timing and looping are preserved. Dropping frames speeds up nothing; the remaining frames are held longer so the animation runs at its original speed.
Would MP4 be better?
Almost always, for anything longer than a couple of seconds — often ten times smaller. Stay with GIF only where video will not play, such as in email.
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