| Platform | Limit | Notes | Source, checked |
|---|---|---|---|
| X (Twitter), mobile apps | 5 MB | GIF is converted to video after upload. | X Help Center, "How to post pictures or GIFs", Sep 2026 |
| X (Twitter), web | 15 MB | Raised from 5 MB in July 2016. | X Help Center, Sep 2026 |
| Discord, free account | 10 MB | Per file. Lowered from 25 MB in 2024. Animated avatars need Nitro. | Discord Support, "What are Nitro & Nitro Basic?", Sep 2026 |
| Discord, Nitro Basic / Nitro | 50 MB / 500 MB | Upload limits by plan. | Discord Support, Sep 2026 |
| Slack custom emoji | 128 KB | Square, 128×128 px recommended. | Slack Help Center, "Add custom emoji", Sep 2026 |
| GIPHY upload | 100 MB, 15 s | Recommends 8 MB or less, 6 s or less, 480p, under 200 frames. | GIPHY Support, "GIF Creation Best Practices", Sep 2026 |
1 MB here means 1,048,576 bytes, which is how the converter's meter counts too. Platforms don't always say which definition they use, so leave a little headroom.
How to get under a limit
- Width first. 480 → 360 px removes about 44% of the pixels. 480 → 240 removes 75%.
- Frame rate. 15 → 10 fps drops a third of the frames. Most reaction clips still read fine at 10.
- Length. Trim the lead-in and the tail. A boomerang nearly doubles the frame count, so trim it harder.
- One palette. "One for the clip" lets unchanged pixels be skipped between frames. On clips with a still background, that alone can halve the file.
- Dithering. Diffusion adds noise that compresses badly. Ordered is smaller; none is smallest (with banding).
- Colours last. Going from 256 to 128 colours usually saves only 10–20%.
Pixel budget: which knob actually shrinks a GIF?
1.00×
480×270 px × 48 frames = 6.2 million pixels, about 24 MB uncompressed in memory while encoding, relative to a 480 px, 12 fps, 4 s clip.
Width counts twice, because height follows it: going from 480 to 240 px leaves a quarter of the pixels. Frame rate and length each scale linearly. Real GIF size tracks this pixel count loosely; detail and motion decide the rest, which is why the converter measures instead of guessing.
Emoji-size GIFs (128 KB)
128 KB is tiny: think 128×128 px, 1 to 2 seconds, 10 fps, 64 colours or fewer, no dithering. Pick the 1:1 crop in the converter, width 128, and the meter will tell you if you've made it.
When to skip GIF altogether
If the platform takes video, an MP4 of the same clip will be far smaller and sharper, and X turns your GIF into video anyway. If it's your own site, animated WebP is a better GIF. GIF wins when it has to play everywhere without a player: email, emoji, wikis, READMEs.
Questions
What is the Discord GIF size limit?
Free accounts can upload files up to 10 MB, which applies to GIFs. Nitro Basic and Nitro raise the upload limit. Discord lowered the free limit from 25 MB to 10 MB in 2024.
What is the X (Twitter) GIF size limit?
X's help centre says animated GIFs can be up to 5 MB on mobile and 15 MB on the web (checked September 2026).
How do I reduce a GIF's file size?
In order of impact: reduce the width, lower the frame rate, trim the length, use one palette for the whole clip, switch dithering from diffusion to ordered or none, and reduce the colour count.
Why did my GIF lose quality after posting?
Many platforms, including X, convert GIFs to MP4 video after upload and serve that instead, and GIPHY resizes GIFs for mobile. Keeping close to their recommended sizes limits the damage.