Ratio Calculator
Scale ratios and find proportional values quickly.
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New A
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Practical proportional scaling
Last updated: March 30, 2026
A ratio calculator helps scale values proportionally, which is essential in recipes, mixtures, design dimensions, and budgeting models.
When one side of a ratio changes, maintaining proportionality requires multiplying the other side by the same factor.
This tool removes mental-math friction and prevents scaling mistakes in daily tasks.
Frequently asked questions
How do ratio scaling calculations work?
If A:B is known and A changes, multiply B by the same scale factor to keep the ratio constant.
Can I use this for recipe scaling?
Yes. It is ideal for scaling ingredients to different serving sizes.
What does reduced ratio mean?
It is the ratio written in smallest whole numbers by dividing both sides by the GCD.