Overview
The Proportion Calculator solves unknown values in a:b=c:d and provides quick ratio scaling for practical tasks like size conversion, recipe adjustment, and price comparison.
Key Features
- Proportion solver: leave one of the four values blank and calculate the unknown instantly.
- Ratio consistency check: shows both a:b and c:d values for quick verification.
- Scale calculator: multiply any original value by a scale factor.
- Change indicator: returns percentage change to help evaluate increase or decrease.
How To Use
- In the proportion section, fill three values and leave only one field blank.
- Click "Solve Unknown" to get the missing value and ratio comparison.
- In the scale section, enter original value and scale factor, then click "Calculate Scale".
Use Cases
- Resize images or design dimensions while keeping ratio.
- Adjust recipe portions for different serving sizes.
- Compare unit prices between packages with different quantities.
- Verify ratio exercises for homework, classes, and exam review.
Notes
- Exactly one unknown field is required in the proportion equation.
- If denominator is 0, or b/d equals 0, ratio expressions are undefined.
- All calculations run locally in your browser.