A free online aspect ratio calculator. Enter width and height to find the simplified ratio, decimal equivalent, and percentage. Scale dimensions up or down by setting a target width or height. Use the common presets for quick 16:9, 4:3, 1:1, 21:9, and more.
Enter the original width and height in pixels.
View the simplified ratio, decimal value, and percentage.
Set a target width or height to scale proportionally.
Use common aspect ratio presets for quick reference.
An aspect ratio is the proportional relationship between width and height of an image, video, or screen. It is expressed as two numbers separated by a colon (e.g. 16:9).
Select "Set Width", enter your target width, and the tool calculates the matching height that preserves the original aspect ratio.
Free online tool — works in your browser, no sign-up required. Start using it right now.
Try It NowResize images to custom dimensions. Set width, height, or scale by percentage. High-quality Canvas output.
Crop images to custom dimensions. Drag to select, choose aspect ratio, and download the result.
Simplify ratios, scale them to target values, and calculate aspect ratio, percentage splits, and decimal equivalents.
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