YouTube Aspect Ratio Calculator
Use this YouTube aspect ratio calculator to prepare standard videos, Shorts, thumbnails and channel artwork. Standard YouTube videos and thumbnails use 16:9, while Shorts use the vertical 9:16 format. Pick the placement first, then calculate the matching dimensions before exporting.
YouTube calculator
YouTube sizes by placement
| Size / ratio | Label | Use-case |
|---|---|---|
| 1920×1080 | 16:9 | Standard Full HD YouTube video |
| 3840×2160 | 16:9 | 4K UHD YouTube video |
| 1280×720 | 16:9 | YouTube thumbnail |
| 1080×1920 | 9:16 | YouTube Shorts |
| 2560×1440 | 16:9 canvas | Channel banner, with center safe area |
YouTube formulas
For standard video: height = width × 9 ÷ 16For Shorts: height = width × 16 ÷ 9For thumbnail: keep 1280×720 unless you need a larger same-ratio source.
Choosing between videos and Shorts
YouTube has two main shape families. Standard videos use 16:9 because the player is widescreen. Shorts use 9:16 because they are designed for full-screen mobile viewing. Thumbnails also use 16:9 so they align with the video player and search result previews.
If you upload a mismatched ratio, YouTube can still process the file, but it may add black bars or show the content smaller than expected. For a clean result, edit standard videos in 16:9 and vertical Shorts in 9:16 from the start.
Think of YouTube as three practical jobs. The first is standard video export, where 16:9 is the default and 1920×1080 is the safe baseline. The second is thumbnail design, where 1280×720 is the normal canvas and text must remain readable at small preview sizes. The third is Shorts, where the correct shape changes to 9:16 and 1080×1920 becomes the better default.
That distinction prevents a common mistake: assuming every YouTube asset uses the same size. You can film a standard video in 16:9, cut a Short in 9:16, and design a thumbnail in 16:9 for the same upload. For the widescreen math use the 16:9 aspect ratio calculator; for Shorts use the 9:16 aspect ratio calculator.
Frequently asked questions
Related calculators and guides
- Aspect ratio calculator — the main calculator with custom ratios
- 16:9 aspect ratio calculator — widescreen video and thumbnail math
- 9:16 aspect ratio calculator — vertical math for Shorts
- Social media image sizes — recommended dimensions per platform
- Aspect ratio vs. resolution — why 1080p and 4K share one shape