100% free · No signup · No watermark · Runs entirely in your browser
Every image has an aspect ratio - the proportional relationship between width and height - and mismatched ratios are why photos get cropped awkwardly. Upload an image and this free image aspect ratio checker simplifies it to its lowest terms (like 16:9 or 4:3), shows the decimal value, and names the closest standard ratio so you know exactly which frames it fits.
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Drop an image here or click to browse
JPG, PNG, WebP, GIF, BMP, SVG - stays on your device
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Simplified ratio
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Decimal value
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Dimensions
Frequently asked questions
Is the aspect ratio checker free?
Yes. Unlimited checks with no signup and no caps, running entirely in your browser.
Are my images uploaded anywhere?
No. The image is decoded locally on your device; nothing is sent to a server or stored.
What does 16:9 actually mean?
It means the width is 16 units for every 9 units of height. A 1920 x 1080 image simplifies to 16:9 because both numbers divide by 120.
My ratio is 1.91:1. Which standard is that?
That is the Open Graph / Facebook link-image ratio (1200 x 630). The tool flags it as closest to 2:1, since 1.91:1 is not one of the 12 classic standards it checks.
Can I use this to plan crops?
Yes. If the tool says your image only closely matches a standard ratio, expect thin crops or letterbox bars when forcing it into that frame.
How do I find the aspect ratio of an image?
Short answer: Upload the image to the checker above. It divides the width and height by their greatest common divisor to give the simplified ratio (for example 1920 x 1080 becomes 16:9), shows the decimal value, and identifies the closest standard ratio from a list of 12 common ones.
Knowing the ratio before you publish prevents surprise cropping on social platforms and video players that enforce fixed frames.
What is the difference between 16:9 and 4:3?
Short answer: 16:9 is a wide rectangle (1.78:1) used for HD video, YouTube and modern screens; 4:3 is a boxier rectangle (1.33:1) from older TVs and classic photography. Neither is better: 16:9 suits video and banners, while 4:3 and 3:2 suit portraits and prints.
The checker tells you which one your image actually is, instead of you guessing from how it looks.
Why does social media crop my photos?
Short answer: Because each platform forces images into its own fixed ratio: Instagram squares to 1:1, Stories to 9:16, link previews to about 1.91:1. If your photo's ratio does not match, the platform crops the overflow automatically, often cutting off heads or text.
Check your ratio first, then crop deliberately with the Image Cropper so you control what gets cut.
