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Ratio Calculator.
Simplify ratios, find equivalent ratios, and solve proportions
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Results update as you type.
Use format: 4:8 or "4 to 8" or 4,8 or 4 8
Equivalent Ratios
How to Use
Ratio: A comparison of two or more numbers showing how many times one value contains another.
Simplifying: Simplify: Reduce a ratio to its smallest whole numbers by dividing by the GCD.
Example: 4:8 simplifies to 1:2 (both divided by 4)
FAQs
How do I simplify a ratio?
To simplify a ratio, divide all parts by their greatest common divisor (GCD). For example, 8:12 simplifies to 2:3 because both are divisible by 4. The simplified ratio shows the same relationship in the smallest whole numbers.
How do I scale a ratio?
To scale a ratio, multiply all parts by the same number. If you want 2:3 scaled so the first number is 10, multiply both by 5 to get 10:15. This maintains the same proportion.
What is a proportion?
A proportion is an equation stating that two ratios are equal (a:b = c:d). For example, if 2:3 = 4:x, then x=6. Proportions are solved by cross-multiplication.
How do I convert a ratio to a percentage?
Divide each part by the sum of all parts, then multiply by 100. For 2:3, the sum is 5. So 2/5 = 40% and 3/5 = 60%.
Cite this calculator
Canonical URL: https://mathify.one/en/math/ratio
Cite as: Mathify. (2026). Ratio Calculator. https://mathify.one/en/math/ratio
Use Cases
Simplify ratios for recipes or mixtures
When a recipe calls for a ratio of ingredients, use the calculator to reduce it to simplest form for easier scaling or to adjust quantities.
Example: Simplify 8:12 to 2:3 for a paint mix.
Scale ratios for resizing or budgeting
If you need to scale a ratio to a new total or a specific component value, the calculator helps find the missing number to keep proportions accurate.
Example: If a model car is 1:24 scale and the real car is 4.8 m, find the model length.
Frequently Asked Questions
- How do I simplify a ratio using this calculator?
- Enter the two numbers of the ratio (e.g., 12 and 18). The calculator will find the greatest common divisor (GCD) and divide both numbers by it, giving you the simplified ratio in its lowest terms, such as 2:3.
- Can this calculator scale a ratio to a target value?
- Yes. If you have a ratio like 2:5 and need to find the equivalent ratio when one part becomes a specific number (e.g., 10), the calculator will compute the missing value to maintain the proportion, giving you 10:25.
- How do I convert a ratio to a percentage or fraction?
- Enter the ratio (e.g., 3:4). The calculator will show the fraction (3/4) and the percentage (75%). It also provides the decimal equivalent (0.75) for quick reference.
Tips & Common Mistakes
Tips
- Always enter the ratio numbers in the order they appear (e.g., first number:second number) to get the correct simplified form.
- Use the scaling feature when you need to find an equivalent ratio with a known part, such as adjusting a recipe for more servings.
- Check the percentage and decimal outputs to understand the ratio's value in different formats, useful for comparisons.
- For ratios with more than two numbers, simplify each pair separately or use the calculator for each pair to ensure accuracy.
Common Mistakes to Avoid
- Entering the numbers in the wrong order, which can lead to an incorrect simplified ratio or scaled value.
- Forgetting to simplify the ratio fully, but the calculator does it automatically, so ensure you use the simplified result for further calculations.
- Assuming the percentage is the first number divided by the second, but it's actually the first number divided by the sum of both numbers (e.g., 2:3 gives 40%, not 66.7%).
Last updated: August 13, 2026