Percentage Calculator
Calculate a percentage of a number, what percent one number is of another, or a percentage change, all in one place.
Runs entirely in your browser, nothing is uploadedCalculate a percentage in three steps
- Pick the calculation you need, a share of a number, what percent one number is of another, or a change between two values.
- Enter the numbers, the result updates live as you type.
- Read the result, percentage increase and decrease are both labeled clearly so the direction is never ambiguous.
Why people use the Percentage Calculator
Everything worth knowing before you dive in.
How it helps
Percentages show up everywhere, a discount at checkout, a grade on a test, a raise on a salary, or a stat comparing two time periods, but the three common calculations each use a different formula. This tool covers all three in one place instead of making you remember which formula applies where.
Built for real use
Finding a percent of a number answers questions like what is 20 percent of 150. Finding what percent one number is of another answers questions like 30 out of 150 is what percent. Percentage change calculates how much a value grew or shrank between two points, clearly labeled as an increase or a decrease so the direction is never confused with the size of the change.
Private by default
Every result updates instantly as the numbers change, useful for quickly checking a discount, a tip, or how much a metric moved without reaching for a calculator app.
Pro tip
When a change looks unusually large, double check which value is the starting point, percentage change is always relative to the from value, not the to value, which is a common source of confusion.
Common questions
What's the difference between percentage change and percentage of?
Percentage of finds a share of a single number, while percentage change compares two values and expresses how much one grew or shrank relative to the other.
Can I use negative numbers?
Yes, the calculator handles negative values, useful for percentage change calculations where a value has decreased.
Why does percentage change show 100% differently than expected?
Percentage change is calculated relative to the starting value, so doubling a number is a 100% increase, not 200%, which trips people up if they expect it to match the final multiple.