Ratio Calculator

About the Ratio Calculator

The Ratio Calculator simplifies any ratio to its lowest terms and solves proportional relationships. Enter two numbers to simplify the ratio using the Greatest Common Divisor, or enter three values to solve for the missing fourth in a proportion.

Ratios express the relationship between two quantities. A ratio of 12:8 simplifies to 3:2, meaning for every 3 units of one quantity there are 2 of the other. This simplification makes ratios easier to understand and compare.

Ratios are used in cooking (ingredient proportions), design (aspect ratios like 16:9), finance (debt-to-income ratios), science (molar ratios), and construction (mix ratios for concrete). This calculator handles all these scenarios with precision.

When This Page Helps

Simplifying ratios by hand requires finding the GCD, which is tedious for large numbers. Solving proportions (a:b = c:?) requires cross-multiplication. This calculator handles both steps clearly.

How to Use the Inputs

1. Enter the first number (A) of the ratio.
2. Enter the second number (B) of the ratio.
3. View the simplified ratio.
4. Optionally enter a third value (C) to solve a:b = c:?.
5. The missing fourth value is calculated automatically.

Example Calculation

Tips & Best Practices

• A ratio of 1:1 means the quantities are equal.
• Aspect ratios for screens: 16:9 (widescreen), 4:3 (traditional), 21:9 (ultrawide).
• In cooking, "2:1 water to rice" means twice as much water as rice.
• Ratios can have more than two parts (e.g., concrete mix 1:2:3 for cement:sand:gravel).
• Financial ratios like P/E (price-to-earnings) are essentially simplified ratios.

Ratios in Everyday Life

Ratios simplify complex relationships. Instead of saying "for 300ml of A, use 200ml of B," you can say "3:2 ratio." This makes scaling intuitive: for 600ml of A, use 400ml of B.

Equivalent Ratios

Multiplying or dividing both parts of a ratio by the same number produces an equivalent ratio. 2:3 is the same as 4:6, 6:9, or 1:1.5. Simplification finds the smallest whole-number equivalent.

Financial Ratios

Businesses track dozens of ratios: debt-to-equity, current ratio, quick ratio, and inventory turnover. Each ratio distills complex financial data into a simple comparison, enabling quick decision-making.

Frequently Asked Questions

• How do I simplify a ratio?

  Divide both numbers by their Greatest Common Divisor (GCD). For 18:24, GCD is 6, so the simplified ratio is 3:4.

• What is a proportion?

  A proportion states that two ratios are equal: a/b = c/d. If you know three of the four values, you can solve for the missing one using cross-multiplication.

• Can ratios have decimals?

  Yes, though they are typically expressed as whole numbers. A ratio of 2.5:5 can be multiplied by 2 to get 5:10, then simplified to 1:2.

• What is the golden ratio?

  The golden ratio is approximately 1:1.618 (or φ). It appears in nature, art, and architecture and is considered aesthetically pleasing.

• How are ratios used in cooking?

  Recipes use ratios for consistent results regardless of batch size. A 3:1 flour-to-sugar ratio scales perfectly whether making 1 cake or 10.

• What is an aspect ratio?

  An aspect ratio describes the proportional relationship between width and height. Common screen aspect ratios include 16:9 for widescreen and 4:3 for traditional displays.