Free YouTube tool
YouTube Shorts Size Checker
A video becomes a Short when it runs 3 minutes or less and is square or vertical. Drop a file in and see whether yours qualifies, and whether it fills the player at 1080 x 1920.
Last updated: 2026-10-25
There is no separate Shorts upload with rules of its own. YouTube decides from the file: a video that runs 3 minutes or less and is square or taller is treated as a Short, and anything else is published as an ordinary video. That makes runtime and shape the two numbers that matter here.
File size almost never does. Shorts share the 256 GB ceiling of every YouTube upload, so a vertical clip runs out of minutes long before it runs out of megabytes. The common miss is a cut that runs a few seconds past 3 minutes, which quietly lands with the ordinary videos instead of in the Shorts feed.
This checker reads the duration, dimensions and size of your file in your browser and compares them with the Short format only. Nothing is uploaded, and the numbers come from YouTube's own help pages.
Your file never leaves your browser. The dimensions are read on your device and nothing is uploaded to us.
Pick a file and every YouTube format is checked against it at once.
The full spec sheet is below, so you can read the numbers without uploading anything.
YouTube video and image specs
Every YouTube surface with its own limits, in one place. These are the platform ceilings, so an upload that clears them still has to clear whatever your publishing tool allows.
YouTube Short
| Max file size | 256 GB |
|---|---|
| Duration | 1 second to 3 minutes |
| Recommended size | 1080 x 1920 |
| Aspect ratio | 9:16 recommended, 1:2 to 1:1 accepted |
| File types | MP4, MOV, WEBM |
- There is no separate Short upload: a video becomes one automatically when it runs 3 minutes or less and is square or taller.
- The same 256 GB upload ceiling applies, so file size is never what stops a Short.
YouTube Standard video
| Max file size | 256 GB |
|---|---|
| Duration | 1 second to 12 hours |
| Recommended size | 1920 x 1080 |
| Minimum size | 426 x 240 |
| Aspect ratio | 16:9 recommended, 1:2 to 1.78:1 accepted |
| File types | MP4, MOV, AVI, WMV, WEBM |
- 256 GB or 12 hours, whichever you reach first. Uploads longer than 15 minutes require a verified account.
- YouTube recommends roughly 8 Mbps for 1080p and 12 Mbps at 60 fps, and re-encodes everything on the way in.
YouTube Thumbnail
| Max file size | 50 MB |
|---|---|
| Recommended size | 3840 x 2160 |
| Minimum size | 640 pixels wide |
| Aspect ratio | 16:9 only |
| File types | JPG, PNG |
- Setting the thumbnail from the YouTube mobile app caps it at 2 MB, against 50 MB from a computer, so export JPG if you plan to set it from your phone.
- Custom thumbnails need a verified YouTube account. When Postify publishes a video it sets your cover image as the thumbnail, fitted to 1280 pixels on the long edge and under 2 MB.
Specs verified 2026-07-31. Networks adjust these without announcing them, so re-check anything you are about to build a whole shoot around.
YouTube export tips
- Trim to 3 minutes or less before you upload. There is no setting that turns a longer video into a Short, only the runtime and the shape.
- Export at 1080 x 1920. Square clips still count as Shorts, but only 9:16 fills the player without bars down either side.
- Keep text away from the edges. Google's published guidance for vertical video ads keeps the top 288 and bottom 672 pixels of a 1080 x 1920 frame clear, and the Shorts safe zone checker draws it. The app itself can differ by device and app version.
Frequently asked questions
How long can a YouTube Short be?
Up to 3 minutes, and the video also has to be square or taller. Both conditions have to hold: a vertical video that runs 3 minutes and 5 seconds is published as an ordinary video, not a Short.
What size should a YouTube Short be?
1080 x 1920 at 9:16. YouTube counts anything from square to vertical as a Short, but 9:16 is the only shape that fills the player.
Is there a file size limit for Shorts?
Only the 256 GB ceiling that applies to every YouTube upload, so file size is never what stops a Short. Runtime and aspect ratio are.
Does this tool upload my video?
No. The file is read in your browser through a temporary link, the same way a local video player opens it. Nothing reaches Postify or anyone else, which is also why a large file is checked instantly.
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