Percentage Calculator
Work out a percentage five different ways, with the working shown so you can check it.
Percentage Calculator
Answer
375.00
- How it is worked out15% of 2500 = 15 / 100 x 2500 = 375
Works out in your browser. Nothing you type is sent anywhere.
In short: Percentage Calculator
Choosing the first mode with 15 and 2500 gives 375.00, and the working shown is 15% of 2500 = 15 / 100 x 2500 = 375. The other modes answer the questions people actually ask: what one number is as a percentage of another, how much something changed, and what a price looks like with a percentage added or taken off.
What is Percentage?
A percentage is a proportion written out of a hundred, so fifteen per cent means fifteen parts of every hundred.
How is Percentage calculated?
A percentage of a number is the percentage divided by a hundred, times the number. To go the other way, divide one number by the other and multiply by a hundred. A change is the difference divided by the figure you started from.
- xthe percentage, or the first number, depending on the mode
- ythe number it applies to
A worked example
| What do you want to work out | What is X% of Y |
|---|---|
| X | 15 |
| Y | 2500 |
| Result | |
| Answer | 375.00 |
| How it is worked out | 15% of 2500 = 15 / 100 x 2500 = 375 |
Every figure in this table is produced by the same calculation the tool above runs.
How to use this percentage calculator
- Choose which of the five questions you are asking.
- Enter the two numbers. The labels change with the mode.
- Read the answer, and the working underneath it.
- Switch mode to ask the same numbers a different question.
Questions people ask
How do I calculate a percentage increase?
Take the difference between the new figure and the old one, divide it by the old one, and multiply by a hundred. Dividing by the old figure is the part people get wrong, and it is why a rise and the matching fall are not the same percentage. The percentage change mode does this for you.
Why is a fall of fifty per cent not undone by a rise of fifty?
Because each percentage is taken of a different starting figure. Halving something and then adding half of what is left leaves you below where you began. Recovering a fall of a half takes a rise of a whole.
What is the difference between percentage points and per cent?
A rate moving from four to six is a rise of two percentage points, and also a rise of fifty per cent. Both are true and they describe different things. Saying which you mean avoids most arguments about numbers.
Can I use this for a discount?
Yes, the fifth mode takes a percentage off a price. For a discount on top of a discount, or one with GST added afterwards, the discount tool handles the whole sequence.
Accuracy and sources
Checked by the Daytoolz team on 16 October 2026. How we check our tools.
Next, people use
- Discount CalculatorWork out what you really pay after one discount
- GST CalculatorAdd GST to a price or work backwards out of a quoted one
- Average CalculatorPaste a list of numbers and see the mean
- Ratio CalculatorSimplify a ratio
- Marks Percentage CalculatorTurn marks into a percentage
- Fraction CalculatorWork with two fractions and get the answer simplified