Aspect Ratio Calculator – Scale Width and Height
Calculate new dimensions from aspect ratio. Scale images or videos proportionally.
About This Calculator
Calculate new dimensions from aspect ratio. Scale images or videos proportionally. Use the calculator above for instant results.
Worked Examples
- Aspect ratio: 16:9 | Decimal: 1.778
Answer: 16:9
- 1280×720 | Same 16:9 ratio maintained
Answer: 1280×720
- Aspect ratio: 64:27 ≈ 21:9
Answer: ~21:9 ultrawide
Who Uses This Calculator?
Maintain aspect ratio when resizing.
Crop images to specific ratios.
Responsive image scaling.
Handle multiple screen resolutions.
Common Mistakes to Avoid
❌ Stretching vs cropping
Maintaining aspect ratio avoids stretch distortion. Cropping may cut content. Letter/pillarboxing adds black bars instead.
❌ CSS aspect-ratio property
Modern CSS: aspect-ratio: 16/9; maintains ratio without JavaScript. No more padding-top hacks needed.
Frequently Asked Questions
Common aspect ratios?
4:3 (old TV). 16:9 (HDTV/YouTube). 21:9 (ultrawide). 1:1 (Instagram). 9:16 (TikTok/Reels). 4:5 (Instagram portrait).
Letterbox vs pillarbox?
Letterbox: black bars on top/bottom (wide content on tall screen). Pillarbox: black bars on sides (tall content on wide screen).
How to crop to 16:9?
If wider: crop width. If taller: crop height. For 1920 wide content at any height, crop height to 1080.