What each platform actually accepts
One page per surface, covering the whole upload envelope rather than the pixel size alone: how long a video may run, what the platform will take as a file, which container and codec it expects, and what its own interface draws over your picture. Frame sizes come from the same table the resize tool uses, so a number here is the number a tool on this site will produce. Everything else was checked against the platforms in September 2026, and anything they decline to publish clearly is marked as disputed rather than guessed at.
- 1080 × 1920 · 9:16Instagram Reel Size and Aspect RatioInstagram Reels are 1080 × 1920 at 9:16, up to three minutes. The full upload envelope — length, file size, format, codec and the safe area the interface covers.Pairs with Resize Video for Instagram
- 1080 × 1920 · 9:16TikTok Video Size and DimensionsTikTok video is 1080 × 1920 at 9:16. The upload ceiling depends entirely on which app you post from — 72 MB on Android, far more from the web. Full specs and limits.Pairs with Resize Video for TikTok
- 1080 × 1920 · 9:16YouTube Shorts Size and Aspect RatioYouTube Shorts are 1080 × 1920 at 9:16 and run up to three minutes. What qualifies a video as a Short, and why its thumbnail is a different shape from a normal upload.Pairs with Resize Video for YouTube Shorts
- 1280 × 720 · 16:9YouTube Thumbnail Size and Format1280 × 720 is still valid, but YouTube now recommends 3840 × 2160 at 16:9. Formats, the 2 MB mobile limit that catches people out, and the 4:5 crop on vertical videos.Pairs with Instant Video Frame Grabber
Why these pages carry a date
Every figure on them is borrowed. Platforms raise length caps, change what their apps will upload and quietly restate their own recommendations, and a specification page that was right two years ago is worse than no page at all — it is wrong with the authority of something that looks maintained. So each set of facts carries the month it was last verified, and the build fails if that date goes stale rather than relying on anyone remembering.
The second habit is admitting what is not knowable. Two of the numbers people most want — Instagram's file size ceiling and TikTok's — are not published in one authoritative place, and the figures circulating contradict each other. Those are marked disputed with an explanation of the spread, which is more useful than a confident number that happens to be someone else's guess.