Not sure why it isn’t working for you, but right now the limit for GIFs on Medium is 5 MB.

For example, here’s a 4.4 MB GIF:

For bigger GIFs you can try to optimize them to go under 5 MB (I use the Online GIF optimizer to add LZW compression) or upload to Gfycat and paste that link. They appear almost exactly as GIFs (they autoplay) and it even works for movies. See this article for many example.

You can see how Gfycat becomes apparent when you hover over the image.

p.s. Sometimes you’re able to upload a file that’s slightly larger than 5MB.

This one appears as 5.1 MB on a mac:

The exact size of it is 5,101,109 bytes.

It seems that Apple uses the metric convention where the M prefix (mega) stands for 1,000,000. Medium however, uses the alternative where k (kilo) is 1024 (or 2¹⁰) and M is 1,048,576 (2²⁰ or 1,024²).

This makes the 5 MB limit actually mean 5,242,880 bytes (more accurately specified as 5 MiB (mebibyte) in ISO units). That’s why the above GIF uploads even though the OS shows it as larger than 5 MB.

p.s.2: Medium also optimizes GIFs if it can (without introducing compression), so sometimes even a file above 5 MiB can upload OK if its optimized size goes under the 5 MiB limit.

Unfortunately it seems you’re having the opposite problem (a file that’s under 5 MiB seems to not upload). Feel free to share the GIF in question with me on Twitter @retronator and I can take a look.

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    I run Retronator and make Pixel Art Academy. https://patreon.com/retro

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