No Results
No results found for your search. Please try another term.
Online Proportion Calculator
Solve a proportion by finding a missing value, check whether two fractions are equal, or simplify a fraction.
Fraction
1
2
=
3
6
Oops! Something went wrong. Please try again.
What Is This Tool?
The Proportion Calculator works with two fractions set equal to each other, like 1/2 = 3/6. Enter the first fraction, then leave one part of the second fraction blank and the tool solves for it. Fill in both parts and it checks whether the two fractions are equal, showing = or ≠. Leave the second fraction empty and it simplifies the first one for you.
How to Use This Tool?
- Enter the numerator and denominator of the first fraction.
- Leave one part of the second fraction blank to solve for it.
- Or fill both parts to check if the fractions are equal.
- Click Calculate to see the result.
Key Features
- Solves for a missing numerator or denominator in a proportion.
- Checks whether two fractions are equal.
- Simplifies the first fraction when the second is left blank.
- Uses cross-multiplication for accurate equality checks.
- Shows the result as a clear pair of fractions.
Examples
- 1/2 = 3/6, so the two fractions are equal.
- In 1/2 = 3/?, the missing denominator is 6.
- In 2/5 = ?/10, the missing numerator is 4.
- 1/2 and 2/5 are not equal, shown as ≠.
Common Use Cases
- Scaling a recipe up or down by a ratio.
- Converting between units using a known proportion.
- Resizing images or models while keeping proportions.
- Checking whether two ratios are equivalent.
- Solving proportion problems for homework.
Tips & Best Practices
- Use whole numbers for the first fraction.
- Leave exactly one part of the second fraction blank to solve for it.
- Fill both parts of the second fraction only when checking equality.
- Leave the second fraction empty to simplify the first.
- Remember the first fraction's values cannot be zero.
Limitations
- The first fraction's numerator and denominator cannot be zero.
- The first fraction must use whole numbers.
- Solved values are rounded for readability.
- It compares exactly two fractions at a time.
Frequently Asked Questions
- What is a proportion?
- A proportion is a statement that two ratios or fractions are equal, such as 1/2 = 3/6.
- How does it solve for a missing value?
- It cross-multiplies the known values, so for 1/2 = 3/?, the missing denominator is 2 × 3 ÷ 1 = 6.
- How does it check if two fractions are equal?
- It cross-multiplies both fractions and compares the products, which avoids rounding errors.
- What happens if I leave the second fraction blank?
- The tool simplifies the first fraction, or doubles it if it is already in lowest terms.
Key Terminology
- Proportion
- A statement that two ratios or fractions are equal.
- Ratio
- A comparison of two quantities, often written as a fraction.
- Cross-multiplication
- Multiplying across a proportion to solve for a missing value or check equality.
- Equivalent fractions
- Two fractions that represent the same value.
- Numerator and denominator
- The top and bottom numbers of a fraction.