Ratio Calculator
Solve proportion problems and scale ratios up or down. Perfect for math problems, recipes, scaling designs, and more.
Ratio Solver (A:B = C:D)
Please provide any three values below to calculate the fourth in the ratio A:B = C:D.
Ratio Scaling Calculator
How could this calculator be better?
We're always looking to improve our tools. Here are some ideas we're considering:
- Add more ratio formats (fractions, decimals)
- Include visual ratio representation
- Add recipe scaling functionality
- Include ratio simplification
- Add sharing functionality for results
Email us at yoursmartcalculator@gmail.com with your suggestions!
Related Calculators
Quick Facts
- •Ratios are used in cooking to scale recipes up or down
- •The golden ratio (1:1.618) appears often in nature and art
- •Aspect ratios (like 16:9) determine screen and image dimensions
- •Financial ratios help analyze company performance
Understanding Ratios
What is a Ratio?
A ratio is a quantitative relationship between two numbers that shows how many times one value contains or is contained within the other. Ratios can compare parts to parts or parts to a whole.
Ratios are written with a colon (:) between the numbers being compared. For example, if there are 3 apples and 4 oranges, the ratio of apples to oranges is written as 3:4.
How to Solve Ratio Problems
To solve ratio problems where you're missing one value in a proportion (A:B = C:D), you can use cross-multiplication:
If A/B = C/D, then A × D = B × C
This means you can find any missing value if you know the other three values in the proportion.
Scaling Ratios
Scaling a ratio means multiplying both parts by the same number to create an equivalent ratio. This is useful for:
- Adjusting recipe quantities
- Resizing images while maintaining proportions
- Creating scale models
- Adjusting chemical mixtures
For example, scaling the ratio 2:3 by a factor of 5 gives you 10:15, which is equivalent to the original ratio.
Common Ratio Applications
Ratios are used in many real-world situations:
- Cooking: Adjusting recipe quantities (e.g., 2 cups flour to 1 cup water)
- Finance: Debt-to-income ratios, price-to-earnings ratios
- Photography: Aspect ratios like 4:3 or 16:9
- Medicine: Drug dosage calculations
- Construction: Mixing concrete or other materials
Frequently Asked Questions
How do I know which value to solve for in a ratio?
In a proportion (A:B = C:D), leave the value you want to find empty or as a question mark. The calculator will solve for the missing value when you click Calculate.
Can ratios have decimals or fractions?
Yes, ratios can use decimal numbers or fractions. However, it's often preferable to convert them to whole numbers by multiplying all terms by the same value.
What's the difference between a ratio and a fraction?
A ratio compares two quantities, while a fraction represents a part of a whole. However, ratios can often be expressed as fractions and vice versa.
How do I simplify a ratio?
To simplify a ratio, divide both numbers by their greatest common divisor (GCD). For example, the ratio 8:12 simplifies to 2:3 when divided by 4.
Can I use this calculator for three-part ratios?
This calculator handles two-part ratios (A:B). For three-part ratios (A:B:C), you would need to solve them as two separate two-part ratios (A:B and B:C).