Ratio Calculator Simplify ratios, solve proportions, and compare ratios — with visual representations and real-world appl...
Ratio Calculator
Simplify ratios, solve proportions, and compare ratios — with visual representations and real-world applications.
A ratio compares two quantities by division, showing how much of one thing there is compared to another.
Ratio Notation**:
- Colon notation**: a:b (e.g., 3:4)
- Fraction notation**: a/b (e.g., 3/4)
- Word notation**: "3 to 4"
Simplifying Ratios**:
To simplify a ratio, divide both terms by their Greatest Common Divisor (GCD).
Example**: 8:12 = 8÷4 : 12÷4 = 2:3
✅ Key Concept**: Ratios can compare parts to parts, parts to whole, or whole to parts.
⚠️ Common mistakes to avoid:
- Adding instead of multiplying**: To scale a ratio, multiply both terms by the same factor
- Confusing ratio with difference**: 2:3 is not the same as "2 less than 3"
- Incorrect proportion setup**: Always maintain the same order (a/b = c/d, not a/b = d/c)
- Zero values**: Ratios cannot have zero as the second term (division by zero)
- Mixed units**: Ensure both quantities use the same units before calculating
✅ Best Practices**:
- Always simplify ratios to their lowest terms
- Use cross-multiplication to verify proportions: a×d = b×c
- When scaling, apply the same factor to all terms in the ratio
- For decimal ratios, multiply by powers of 10 to eliminate decimals before simplifying
Ratios are essential in:
- Cooking**: Recipe scaling (2 cups flour : 1 cup sugar)
- Photography**: Aspect ratios (16:9, 4:3, 3:2)
- Finance**: Financial ratios (debt-to-equity, price-to-earnings)
- Medicine**: Drug dosage ratios (5mg per kg of body weight)
- Construction**: Mix ratios (1 part cement : 2 parts sand : 3 parts gravel)
📊 Example Use Cases**:
- Recipe scaling**: Original ratio 2:3, scale by 4 → 8:12
- Map scale**: 1:50,000 means 1cm on map = 50,000cm in real life
- Business**: Profit margin ratio of 0.25 = 25% profit
- Photography**: 16:9 aspect ratio for widescreen displays
➡️ Simplify Ratio
"Simplify 8:12" → 2:3 (0.6667, 66.67%)
➡️ Solve Proportion
"3:4 = 9:D" → D = 12
➡️ Compare Ratios
"2:3 vs 4:6" → Equivalent (both equal 0.6667)
➡️ Scale Ratio
"Scale 5:8 by factor 3" → 15:24
Note: All calculations handle decimal inputs and automatically simplify results. For proportions, the calculator solves for the missing fourth term using cross-multiplication.