YouTube upload bitrate: 8 Mbps at 1080p vs a 1080x1920 Short

YouTube's recommended bitrate for 1080p SDR is 8 Mbps at standard frame rates and 12 Mbps at high frame rates. The page lists its numbers by resolution and does not give a separate row for 1080x1920 vertical video. YouTube says only that the player adapts to vertical and square. A Short can be up to 3 minutes, so a file at the 1080p recommendation weighs about 180 MB at the limit.

The recommendation

Shorts, from the Shorts upload page

The Shorts upload page says Shorts can be up to 3 minutes, square or vertical, and up to 15 short videos can be uploaded at a time. That page lists no pixel sizes.

Arithmetic for file size

Size in megabytes is megabits per second times seconds divided by 8. Video only, using the page's 1080p figures:

Reading the table honestly

The numbers above are YouTube's recommendations, not minimums, and a lower-bitrate file may still upload. The page does not say what happens below them. Use them as a target for sources you control and as a comparison for what you download.

If your measured bitrate is far above the recommendation, the file is bigger than it needs to be, which only costs upload time. If it is far below, check for visible blocking before you publish.

What Sume gives you

Timeline 1.0 renders 1080x1920 MP4 by default and, when you omit output.fps, uses the rate of the sources. Video trim with precision: exact can conform output.fps to 24, 25, 30 or 60. Those four are on YouTube's list. 48 and 50 are on YouTube's list but not among trim's options.

The Sume docs do not state a target bitrate for either tool, so measure the file you get and compare it with the table before upload.