Aspect Ratio Calculator
Calculate width or height for any aspect ratio in seconds. Choose a preset or custom ratio and preview the resulting dimensions instantly.
Presets
Quick sizes
Change either pixel field and the other updates to keep the ratio. Ratio fields stay editable — editing them switches the preset to Custom.
Common ratios
YouTube, modern TVs, presentations, and most laptop displays.
TikTok, Reels, Shorts, and phone-first vertical video.
Ultrawide monitors and cinematic widescreen frames.
Photography, classic monitors, and social avatars.
Frequently Asked Questions
What is aspect ratio?
It is the width-to-height proportion of an image or frame. 16:9 means 16 units wide for every 9 units tall.
How do I calculate aspect ratio?
Divide the width by the height to get the ratio between the two dimensions. With this calculator, you can enter a width or height and automatically get the matching dimension for ratios such as 16:9, 9:16, 4:3, or 1:1.
What resolution is 16:9?
Common 16:9 resolutions include 1280×720, 1920×1080, 2560×1440, and 3840×2160. You can also enter any custom width to calculate the corresponding 16:9 height.