A GIF that's too big doesn't fail loudly on Tumblr — it posts fine and then sits there as a still image. Drop your GIF below to check its size, width, and frame count before you find out the hard way.
Drop a GIF here, or click to choose one
Nothing is uploaded — the file is read in your browser and never leaves your device.
What happens to your GIF at each size, and why the number that matters isn't the one Tumblr advertises.
Tumblr won't compress a GIF below 3 MB. What you upload is exactly what people see, and it reblogs cleanly across every theme and device. This is the target to aim for.
Still within Tumblr's stated limit for compressed GIFs, but it will be re-encoded on the way in. Expect some quality loss, especially on gradients and film grain.
Tumblr will try to compress it down. If the result can't be served, Tumblr falls back to displaying only the first frame — your GIF posts successfully but sits there motionless.
Past Tumblr's hard maximum. The upload fails. Cut frames, crop the canvas, or reduce the colour palette to get under the line.
Tumblr recommends GIFs no wider than 540px, which is the dashboard column width. Anything wider gets scaled down for display while still costing you the full file size.
Limits are Tumblr's own, from the Tumblr Help Center. Sizes here use 1 MB = 1,000,000 bytes, the stricter reading, so anything this tool passes is safe either way.
Three levers control GIF file size, and they're not equally useful. Frame count is the big one — halving the frame rate roughly halves the file, and most GIFs read fine at 12fps. Trimming a second off the clip does the same job.
Dimensions come second. Since Tumblr displays at 540px wide, anything beyond that is paying for pixels nobody sees. Resizing a 1280px GIF down to 540px cuts the file dramatically.
Colour depth is the fine-tuning pass. Dropping from 256 to 128 or 64 colours saves real space, and on flat-colour animation you often can't see the difference. On film grain and gradients you can, so use this one last.
Once your GIF posts properly, the next question is whether anyone sees it — which comes down to when you post and how you tag. We covered the timing side in finding your best time to post, and what Tumblr does and doesn't measure in does Tumblr have analytics.
10 MB is the hard maximum — above that the upload is rejected. But the practical limit is lower: GIFs under 3 MB aren't compressed at all, and Tumblr states that compressed GIFs should be no larger than 5 MB. Between 5 MB and 10 MB you're relying on Tumblr's compression succeeding.
The usual cause is file size. When a GIF is over 5 MB and Tumblr can't serve the compressed version successfully, it displays only the first frame instead. The post publishes normally, so there's no error to tell you what went wrong — it just looks like a still image. Getting the file under 5 MB, ideally under 3 MB, fixes it.
Tumblr recommends no more than 540 pixels wide, which matches the dashboard column. Taller is fine — vertical GIFs and stacked GIF sets work well. Going wider than 540px doesn't improve how it looks on the dashboard, but it does inflate your file size, which pushes you toward the compression thresholds.
Yes. Tumblr converts uploaded GIFs to the GIFV format for playback, which is why a GIF can look different on Tumblr than it did in your editor. This conversion is also what fails when a large GIF ends up showing only its first frame.
In order of how much they save: cut the frame count (drop the frame rate or trim the clip), reduce the canvas width to 540px, and lower the colour palette from 256 to 128 or 64 colours. Frame count is almost always the biggest win — a two-second GIF at 12fps is a fraction of the size of the same clip at 24fps.
No. The file is read in your browser using the File API and parsed locally. Nothing is sent to a server, nothing is stored, and the tool works with your network disconnected.
Every plan includes all core analytics features and a 7-day free trial. Pick the plan that fits your needs.