Free Percentage Calculator
Work out any percentage in seconds. Find a percent of a number, what percent one number is of another, the increase or decrease between two values, or add and subtract a percentage.
What is a percent of a number?
20% of 150
- Number
- 150
- Percentage
- 20%
- Result
- 30
Handy for quick checks and reports. Double-check the figure before you rely on it for anything official.
Work out a percentage in four steps.
Choose what you want to work out, type your numbers, and read the answer with the working underneath. Everything updates as you type.
Pick what to work out
Choose a percent of a number, one number as a percent of another, the change between two values, or adding and subtracting a percentage.
Enter your numbers
Type the two values the mode needs. There is nothing to submit, everything updates as you type.
Read the result
See the answer big and clear, with the working spelled out underneath so you can check it at a glance.
Copy or reuse it
Copy the full result in one tap for a message, a spreadsheet or your notes.
More than just percent of a number.
Most percentage calculators only do one thing. This one runs the numbers in every direction, so you can start from whatever you already know.
% of a number
The everyday one. Work out what 20% of 150 is, or any percent of any number.
One number as a % of another
Find what percentage one number is of another, like a score out of a total or a part of a budget.
Percentage change
See the percentage increase or decrease between an old value and a new one, with the raw difference too.
Add a percentage
Add a percentage on top of a number. Handy for a tax, a tip or a markup.
Subtract a percentage
Take a percentage off a number to get the reduced value, and see the amount removed.
Percentage of a total
Turn a part and a whole into the share it represents, as a clean percentage.
How the percentage maths works.
The formulas behind each mode, with a worked example. Once you have seen them written out, they are easy to do by hand too.
% of a number
Result = Number × Percent ÷ 100
Example: 20% of 150 is 150 × 20 ÷ 100, which is 30.
One number as a % of another
Percent = Part ÷ Whole × 100
Example: 150 out of 200 is 150 ÷ 200 × 100, which is 75%.
Percentage change
Change = (New - Old) ÷ Old × 100
Example: Going from 150 to 200 is (200 - 150) ÷ 150 × 100, a 33.33% increase.
Add or subtract a percentage
Add: Number × (1 + Percent ÷ 100)
Subtract: Number × (1 - Percent ÷ 100)
Example: 150 plus 20% is 180. 150 minus 20% is 120.
Numbers that work out themselves.
This tool is great for a one-off percentage. But when the same maths runs across invoices, payroll, stock and reports every day, you want it built in, not typed out by hand each time. That is the kind of custom software and dashboards we build at Techliphant, shaped around how your business actually works.
Working out a price cut? Try the discount calculator.
Common percentage questions.
It is a free online tool that works out percentages for you. You type your numbers and it shows the answer with the working, so you can find a percent of a number, what percent one number is of another, the change between two values, or the result of adding or subtracting a percentage.
Multiply the number by the percentage and divide by 100. So Result = Number × Percent ÷ 100. For example, 20% of 150 is 150 × 20 ÷ 100, which is 30. Set the tool to "% of a number" and it does this as you type.
Divide the first number by the second and multiply by 100. So Percent = Part ÷ Whole × 100. For example, 150 out of 200 is 150 ÷ 200 × 100, which is 75%. The "One number as a % of another" mode works this out for you.
Subtract the old value from the new value, divide by the old value, and multiply by 100. So Change = (New - Old) ÷ Old × 100. A rise from 150 to 200 is a 33.33% increase. If the answer is negative, it is a decrease. Use the "Percentage change" mode and it labels which one it is.
Multiply the number by one plus the percentage as a decimal: Number × (1 + Percent ÷ 100). So 150 plus 20% is 150 × 1.2, which is 180. This is the same maths you use to add a tax, a tip or a markup.
Multiply the number by one minus the percentage as a decimal: Number × (1 - Percent ÷ 100). So 150 minus 20% is 150 × 0.8, which is 120. The "Subtract a percentage" mode also shows the amount that was taken off.
A percentage change is relative to the starting value, while a percentage point is a plain difference between two percentages. If a rate goes from 10% to 15%, that is a rise of 5 percentage points, but a 50% increase in relative terms. This tool works out the relative percentage change.
Divide the top of the fraction by the bottom to get a decimal, then multiply by 100. So 3 divided by 4 is 0.75, which is 75%. Any decimal becomes a percentage the same way, by multiplying by 100. The "One number as a % of another" mode does this if you enter the two parts of the fraction.
Yes on both. It is free, there is no sign-up, and it runs entirely in your browser. Nothing you type is sent anywhere or saved, so your numbers stay on your own device.
It is great for a quick percentage on a quote, a report or a price check. When you need percentages applied automatically across invoices, payroll, stock and dashboards, that belongs in software built around how your business runs. That is the kind of system we build at Techliphant.
Private by design: this calculator runs entirely in your browser, so nothing you type is uploaded or stored. It is provided free for quick estimates and educational use. For anything official, confirm the final figures against your own records.
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