Aspect Ratio Calculator
Turn any width and height into a simplified aspect ratio, lock a preset like 16:9 to auto-compute the other dimension, and browse common resolutions.
Processed locally in your browser — nothing is uploaded.
Results
- Simplified ratio
- 16:9
- Decimal
- 1.7778
Width divided by height.
About Aspect Ratio Calculator
Enter a width and height to get the simplified whole-number ratio (via greatest common divisor) and its decimal form. Lock one of the preset ratios — 16:9, 4:3, 21:9, 1:1, 3:2, or 9:16 — and editing either dimension recomputes the other automatically.
A locked preset also shows its common real-world resolutions, from VGA up to 4K, so you can jump straight to a standard size.
Common uses
- Resize a video thumbnail while keeping 16:9
- Work out what height a 1200 px-wide 3:2 image needs
- Check what ratio an odd image size actually is
Example
Input
1920 × 1080
Output
16:9 · decimal 1.7778
Limitations
- Ultrawide "21:9" monitor resolutions are exactly 64:27, so they will not simplify to 21:9