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LunaCalc

Math

Percentage Calculator

Solve common percentage, ratio and percent-change problems.

Calculator
What is p% of x?
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x is what percent of y?
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x is p% of what?
What is x increased/decreased by p%?
% ?

About this calculator

This percentage calculator handles everyday percent problems such as finding a percentage of a number or converting between parts and wholes.

Formula notes

Core relationships include part = whole x percent / 100 and percent = part / whole x 100.

Worked examples

  1. Example: 15% of 240 is 36, because 240 x 0.15 = 36.
  2. If 54 of 240 survey responses choose an option, the share is 54 / 240 x 100 = 22.5%.

How to use it

  1. Enter the known values for the percentage problem.
  2. Choose the calculation that matches your question.
  3. Use the result for discounts, grades, ratios, or reports.

Frequently asked questions

Can I calculate percentage increase here?

Use this tool for base percentage math, and the percentage-change calculator for increase or decrease between two values.

What does a percentage above 100% mean?

It means the compared amount is larger than the chosen whole. For example, 150 is 150% of 100.

Limits and interpretation

  • The denominator must represent the correct whole or baseline; changing it changes the meaning of the percentage.
  • Percentages from rounded counts may not sum to exactly 100%, and weighted survey results need weights rather than raw counts.

References