Calculate pixel dimensions for any aspect ratio
Enter a width and the tool calculates the matching height for your chosen aspect ratio — or enter any two of the three values and get the third. Preset buttons cover common ratios for social media, cinema, print, and display. Use it to resize images and video frames without distortion.
Use this tool freeBrowser tool
Aspect ratio calculator
Enter any two values. The calculator runs locally and instantly in your browser.
Live shape preview
How to use
Select or enter a ratio
Click a preset button or type a custom ratio like 16:9 or 4:3. The calculator locks the ratio immediately.
Enter a dimension
Type a width or height in pixels. The tool calculates the matching dimension to maintain the ratio.
Copy the result
Click the width × height values to copy them. Use the scaling table to explore alternative resolutions at the same ratio.
Features
Three-way calculator
Enter any two of width, height, and aspect ratio and the tool calculates the missing value. Lock any field and adjust the others to explore dimensions interactively.
Social media presets
One-click presets for Instagram (1:1, 4:5, 9:16), YouTube (16:9), Twitter/X header (3:1), Facebook cover (205:78), and more. Each preset fills in the recommended pixel size.
Custom ratio input
Enter any ratio as W:H — including non-standard values like 2.39:1 for cinema or 3:2 for DSLR sensors. The calculator works with integers and decimals.
Scaling table
View a table of common resolutions that share the selected aspect ratio — from thumbnail sizes up to 8K. Copy any row to quickly get the exact dimensions you need.
After this task
After this free tool, open Ai Enhance for the next AI editing workflow.
Continue with Ai EnhanceSpecifications
| Input | Width, height, or aspect ratio |
| Presets | 15+ social, film, and print ratios |
| Custom ratio | Any W:H including decimals |
| Output | Pixel dimensions, scaling table |
| Max dimension | 99999 px |
| Processing | Client-side (instant) |
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Common questions
What aspect ratio should I use for Instagram?
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Instagram supports 1:1 (square), 4:5 (portrait, recommended for feed), and 9:16 (Stories and Reels). The 4:5 ratio takes up the most feed space and generally performs best for engagement.
How do I find the aspect ratio of an existing image?
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Enter the image's width and height in the calculator and leave the ratio field empty. The tool will simplify the dimensions to the lowest-term ratio — for example 1920 × 1080 simplifies to 16:9.
Does this tool resize my image?
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No. This is a calculator that gives you the correct pixel dimensions. To actually resize an image, use a resizing tool with the dimensions this calculator provides.
Ready to resize your image?
AI Enhance can resize and upscale images to any dimension while keeping details sharp. Calculate the right size here, then resize the image with AI precision.
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