Ratio Calculator
Three ratio tools in one. Simplify a ratio with two or more terms to its lowest whole numbers, solve for a missing value in A:B = C:D using cross-multiplication, or divide a total into parts that follow a ratio.
How to use the Ratio Calculator
- Choose Simplify, Solve or Split a total.
- Enter the ratio (e.g. 12:18) or fill in three of the four proportion boxes.
- For splitting, enter the ratio and the total amount.
- Press Calculate to see the result and a check of the working.
Features
- Simplifies ratios with any number of terms, including decimals
- Shows the ratio in 1 : n form
- Solves any missing term in A:B = C:D
- Splits totals proportionally, e.g. 500 in the ratio 2:3
Benefits
- Scale recipes, mixtures and screen aspect ratios correctly
- Divide costs or profits fairly between partners
Frequently asked questions
How are ratios simplified?
Every term is divided by their greatest common divisor. 12:18 has a GCD of 6, so it simplifies to 2:3. Decimal ratios are first multiplied by a power of 10 to make whole numbers.
How is a proportion solved?
By cross-multiplication: if A:B = C:D then A × D = B × C. With 2:3 = 8:D, D = 3 × 8 ÷ 2 = 12.
How do I split money in a ratio?
Add the ratio terms, divide the total by that sum, then multiply by each term. 500 in the ratio 2:3 is 200 and 300.
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