Free Aspect Ratio Calculator
Enter one side, get the other. Solve any aspect ratio in pixels, millimetres and inches — with presets for every ad placement.
Solving one ratio is arithmetic. Rendering every ratio for every SKU is Xeli.
Try XeliThat is the 16:9 ratio — The standard landscape video ratio — 1920×1080 px, 1.778:1 — used by YouTube in-stream, Meta landscape video and every HD display.
1920×1080 is one size. Xeli renders every ratio a campaign needs from a single master — per SKU, safe zones respected.
Try XeliFree forever for stores under 10 SKUs — Xeli does this for your whole catalog, across every placement.
How to use Free Aspect Ratio Calculator
- 1Pick a ratio
Choose a preset like 16:9 or 4:5, or type your own ratio width and height.
- 2Enter the side you know
Type a width or a height in pixels — the other side solves instantly.
- 3Read the conversions
Copy the pixel result, or set a DPI to get the millimetre and inch equivalents.
Who this is for
- Designers converting a master creative into every placement ratio
- Performance marketers checking a size matches the placement spec before upload
- Print and packaging teams converting pixel dimensions to mm at 300 DPI
Frequently asked questions
How do I calculate an aspect ratio?
Divide the width by the height to get the decimal ratio. To find a missing side, divide the width by that decimal to get the height, or multiply the height by it to get the width.
What is 16:9 in pixels?
1920×1080 px. Other exact 16:9 sizes are 1280×720, 2560×1440 and 3840×2160.
Does it convert to mm and inches?
Yes — set your DPI (300 for print, 72 for screen) and the calculator shows the physical size in both millimetres and inches.
Which ratio should I use for ads?
4:5 for feed, 9:16 for Stories and Reels, 1:1 for marketplaces, 1.91:1 for link ads and og:image, 16:9 for landscape video.
Xeli reframes one master creative into every ratio each placement needs — automatically, with safe zones respected.
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