Any percentage question, with the number you are taking it from always in view.
Your answer
Type your two numbers and the answer appears here, with each step and a picture of the share.
The working
Good to know
Results are rounded for reading. Tax, finance, grades and statistics can have their own rounding rules, so check the rule that applies to you.
Questions
For a percent of a number, divide the percent by 100 and multiply: 2.5 ÷ 100 × 4,000,000 = 100,000. For what percent one number is of another, divide and multiply by 100: 160 ÷ 200 × 100 = 80%. The % of tab does the first and the What % tab the second.
Multiply the number by the percentage, then divide by 100. 15% of 80 is 80 × 15 ÷ 100 = 12.
Divide the part by the whole and multiply by 100. 45 out of 60 is 45 ÷ 60 × 100 = 75%. The whole cannot be 0.
Take the new value minus the old value, divide by the old value, and multiply by 100. Going from 160 to 200 is (200 − 160) ÷ 160 × 100 = a 25% increase.
Each percentage is taken from a different starting number. 160 up 25% is 200, but 200 down 25% is 150. To get from 200 back to 160 you only need a 20% fall.
Divide by 1 plus the rate. A $275 price that includes 10% GST was $275 ÷ 1.10 = $250 before tax, so the GST is $25. Taking 10% off $275 gives $247.50, which is wrong.
Percentage points are the plain gap between two percentages. A rate going from 10% to 12% rises by 2 percentage points, which is a 20% increase in the rate itself.
Printout
One page: your answer and working, plus a ready-reckoner of common percentages of your number for the shop, the desk or the classroom.
For spreadsheets and code
In a spreadsheet: =B1*A1/100 for a percentage of a number, =(B1-A1)/A1 formatted as % for a change, =A1/(1+B1/100) for the amount before.
number = 200
percent = 25
old, new = 160, 200
print(number * percent / 100) # percentage of a number
print((new - old) / abs(old) * 100) # percentage change
print(275 / (1 + 10 / 100)) # before it was addedBoth use your current numbers from the calculator.
Name: ______________________ Date: 2 November 2026
| Question | Percentage of a number |
|---|---|
| Answer | 25% of 200 = 50 |
| Working | 200 × 25 ÷ 100 = 50 |
| Answer | 50 |
| What is left | 150 |
| As a decimal | 0.25 |
| As a fraction | 1/4 |
| 1% of it | 2 |
| 10% of it | 20 |
| 1% = 2 | 5% = 10 | 10% = 20 | 12.5% = 25 |
| 15% = 30 | 20% = 40 | 25% = 50 | 30% = 60 |
| 33.33% = 66.66 | 40% = 80 | 50% = 100 | 75% = 150 |
Percentage of: number × % ÷ 100 · What %: part ÷ whole × 100 · Change: (new − old) ÷ old × 100 · Before it was added: total ÷ (1 + % ÷ 100)
Rounded for reading. calculationtime.com/calculators/percent-calculator/ · printed 2 November 2026
Everyday percentages
For a restaurant bill, decide first whether the rate applies to the amount before or after tax, then use that amount as the total here.
Sources
Printables
Percent CalculatorPin it