Ratio Calculator simplifies ratios to their lowest terms, scales ratios to target values, and solves missing-value proportion problems (if A:B = C:x, find x). It handles two-term and multi-term ratios, converts between ratio notation (3:4), fraction notation (3/4), and decimal notation (0.75), and supports aspect ratio calculations for image and video dimensions. The tool also finds equivalent ratios and determines whether two ratios are proportional.
Designers calculating aspect ratios, engineers working with scale drawings, and cooks adjusting recipe proportions. The tool runs entirely in your browser — your data never leaves your device.
Learn more about related topics: Proportion, Aspect ratio, GCD, Scale factor.
Ratio Calculator is a free, browser-based developer tool on AIDToolStack. Calculate and simplify ratios, find equivalent ratios and missing values. It requires no installation or sign-up and works entirely in your browser.
Yes, completely free. Ratio Calculator has no usage limits, no account requirements, and no hidden fees. Use it as often as you need.
No, all processing happens locally in your browser. Your data never leaves your device and nothing is sent to any server.
Yes, it works in any modern browser on both desktop and mobile devices. No app download required — just open the page and start using it.
AIDToolStack tools run entirely in your browser with no server processing. This means faster results, complete privacy, and zero downtime. There are no ads blocking your workflow, and everything is free with no sign-up required.
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