Percentage Calculator
Quickly calculate percentages, percentage change, and percentage of a total.
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How to use this calculator
Multiply your number by the percentage and divide by 100.
- 1
Enter the number you want to find a percentage of.
- 2
Enter the percentage you want to calculate.
- 3
The result appears instantly below the inputs.
Frequently asked questions
What exactly does this calculator return?
It finds the given percentage of a number, then shows that number increased and decreased by the same percentage. For 200 at 15% you get 30.00, 230.00 and 170.00. It does not work out "what percent is A of B" or percentage change between two values; for those you divide by hand using the formulas on this page.
How many decimals does it show?
Always two, rounded from the exact product. 8.5% of 59.99 is 5.09915, which appears as 5.10, so 59.99 plus that amount shows as 65.09. If you are chaining several steps, keep the unrounded figure in your head or on paper and round only at the end.
Can I enter a percentage above 100 or a negative one?
Yes. 150% of 50 returns 75.00, and "50 decreased by 150%" returns -25.00 because the subtraction simply goes below zero. A negative percentage flips the direction: -10% of 120 is -12.00, and the "increased by" row then shows 108.00.
Why is a 20% rise followed by a 20% fall not back to the start?
The second percentage is taken of a different base. 100 up 20% is 120, and 20% of 120 is 24, so the fall lands on 96, not 100. To undo a 25% increase you need a 20% decrease, because 1.25 × 0.8 = 1.
How do I work out a percentage change between two numbers?
Subtract the old value from the new one, divide by the old value and multiply by 100. Going from 80 to 100 is (100 − 80) ÷ 80 × 100 = 25%. You can check it with this calculator: 25% of 80 is 20.00 and "80 increased by 25%" is 100.00.
Is "percent" the same as "percentage points"?
No. A rate moving from 4% to 6% rose by 2 percentage points but by 50 percent in relative terms. This calculator handles the relative kind only: the percentage you enter is always applied to the number you enter.
What happens if a field is left blank?
A blank field is read as 0, so the result is 0.00 and the increased and decreased rows equal the original number. Typing text that is not a number shows an "Enter valid numbers" message instead of a result.
Percentage calculator — find a percent of any number and apply it as a rise or a fall
What the three result lines mean
Percent means "per hundred", so 15% of 200 is 15 ÷ 100 × 200 = 30. The calculator reports that amount, then adds it to the original and subtracts it from the original. Those two extra lines are the answers people usually need for a mark-up, a discount, a tip or a pay rise, so you do not have to add or subtract separately. Because the second and third lines use the same percentage, they are mirror images around the original number, which makes it easy to see the size of a swing in either direction before committing to a price or a budget.
Worked example: a 25% discount
A jacket costs 80 and is marked down 25%. Entering 80 and 25 gives 20.00 as the saving and 60.00 as the price after the discount. The same inputs also show 100.00 in the "increased by" line, which is the 80 plus a 25% mark-up. The pair 60 and 100 is a reminder that +25% and −25% do not cancel each other.
Worked example: tax on an odd price
For a price of 59.99 and a rate of 8.5%, the tool shows 5.10 for the percentage amount and 65.09 for price plus that amount. The exact product is 5.09915, so the displayed figures are rounded to cents. A till or invoice system may round at a different step, which can move a total by a cent. If you need the figure for a receipt, use the unrounded product and round once at the very end rather than rounding each intermediate step; stacking several rounded steps is the usual reason two systems disagree by a small amount.
Common rates applied to 200
The table lists what the calculator returns for five everyday rates. Notice that each step of 5 percentage points adds 10 to the amount, because 1% of 200 is exactly 2.
| Percent | Amount | Increased by | Decreased by |
|---|---|---|---|
| 5% | 10.00 | 210.00 | 190.00 |
| 10% | 20.00 | 220.00 | 180.00 |
| 15% | 30.00 | 230.00 | 170.00 |
| 20% | 40.00 | 240.00 | 160.00 |
| 25% | 50.00 | 250.00 | 150.00 |
Finding the percentage when you know the parts
To learn what percent A is of B, divide A by B and multiply by 100: 30 out of 200 is 15%. For change over time use (new − old) ÷ old × 100. Neither is automated here, but you can verify your answer by entering the percentage you found and checking that it reproduces the number you started with. The reverse question, finding the original price before a known percentage was applied, is also division: divide the final price by 1 plus the rate for a rise, or by 1 minus the rate for a fall. A price of 60 after a 25% discount started at 60 ÷ 0.75 = 80.
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Results are estimates for informational purposes only and do not constitute professional financial, medical, legal, or technical advice. Read full disclaimer →