Creative Tools
Aspect Ratio Calculator
Enter pixel or millimetre dimensions to get the reduced ratio and common labels.
Find the aspect ratio
Social crops, print layouts and video frames all enforce ratios such as 16:9, 1:1 or 4:5. Enter one dimension to derive the other, or simplify a freeform width and height into a clean ratio before you commission photography or export from a design tool. Matching the target ratio early avoids unexpected letterboxing, stretched faces or last-minute squeezes in Photoshop. Platforms change safe zones and recommended crops; treat common ratios as a starting point and confirm against the placement you are buying. For print output at a chosen DPI, continue with the print size calculator. Pixel-perfect brand guidelines still need a visual check after the maths, especially when logos have minimum clear space. Story and reel vertical frames (9:16) behave differently from feed posts — export masters in the native ratio rather than cropping a 16:9 timeline at the last minute whenever you can. Export masters at the native ratio for each placement whenever deadlines allow; cascading crops from a single landscape hero rarely look intentional. Brand templates should lock ratio early so agencies stop delivering the wrong shape.
Worked example
You need a 4:5 Instagram portrait that is 1080 px wide. Height = 1080 × 5 ÷ 4 = 1350 px. A landscape photo that is 6000 × 4000 (3:2) cannot fill 4:5 without cropping; decide which subject stays in frame before you upscale. For a 16:9 YouTube thumb at 1280 px wide, height is 720 px — classic HD frame maths.
Limits and assumptions
Ratio alone does not guarantee sharpness; resolution and compression still matter. Platform UI chrome can cover edges — leave safe margins beyond the pure ratio. Anamorphic footage and non-square pixels need interpretation before you trust width÷height.
Frequently asked questions
How do I get a 16:9 width from a height?
Multiply height by 16/9. The calculator does this from whichever side you lock.
What ratio should I use for Instagram feed posts?
Common choices include 1:1 and 4:5. Confirm against current platform recommendations for your placement.
Does aspect ratio change file size?
Not by itself — resolution and compression do. Ratio only sets the shape.
How do I simplify 1920×1080?
Divide both by 120 to get 16×9. The tool returns the reduced ratio from any width and height pair.
Should thumbnails match video ratio?
Usually yes for YouTube 16:9. Some networks letterbox — check the destination before exporting.