Is Ratio Calculator free to use?

Yes, Ratio Calculator is completely free. No account, no sign-up, and no hidden fees required.

Is my data safe when using Ratio Calculator?

Your data never leaves your device. All processing happens locally in your browser — nothing is uploaded to any server.

Calculators

Solve a:b = c:d for any missing value, simplify ratios, and check proportional relationships

Trusted by 10k+ developers

Solve a:b = c:d. Leave exactly one field empty to find the missing value.

Result

D = 16

Simplified ratio: 3 : 4

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