# Ratio Calculator

> Simplify ratios, scale them, and solve for a missing value in a proportion.

To work with ratios, choose whether to simplify, scale or solve a proportion. Simplification handles decimals by scaling to whole numbers first, and the result is also shown as a fraction, decimal, percentage and as parts of the whole.

**URL:** https://convertto.tech/t/ratio-calculator
**Category:** Calculators (https://convertto.tech/c/calculators)
**Privacy:** Runs entirely in the browser; no upload
**Cost:** Free, no sign-up
**Last updated:** 2026-08-01

## Key facts

- **Privacy:** Runs entirely in your browser — nothing is uploaded
- **Cost:** Free, unlimited, no sign-up

## How to use

1. Choose the calculate.
2. Set the a.
3. Set the b.
4. Set the c (or factor).
5. The result appears immediately — copy or download it.

## FAQ

### What is the difference between a ratio and a fraction?

A ratio compares parts to each other; a fraction compares a part to the whole. In a 2:3 ratio there are five parts in total, so the first quantity is two-fifths of the whole — not two-thirds.

### How do I scale a recipe with ratios?

Divide the target quantity by the total number of parts to get the value of one part, then multiply each side of the ratio. For a 2:3 ratio making 500g, one part is 100g, giving 200g and 300g.

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