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Percentages

Percentage of a Number Calculator

Find any percentage of any number with the full step-by-step working shown. Covers tips, discounts, tax, exam marks, and any "what is X% of Y?" calculation.

Percentage of a number calculator

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Related Calculators
Percentage Increase / Decrease → Reverse Percentage → All 3 Types Together →

Step by step calculations

Enter values in the calculator to see the step by step calculations.

Percentage of a Number Explained

Core concepts, classroom applications, and plain-English explanations for all audiences.

The calculation you use most without realising

Leaving a 15% tip on a £48 restaurant bill. Working out 20% VAT on a £320 quote from a tradesperson. Calculating a 30% off sale on an £85 jacket. Finding 25% of your daily recommended calorie intake on a food label. These are all "percentage of a number" — probably the most frequently used calculation in adult life.

Worked example

"A restaurant bill is £64. You want to leave a 15% tip."

Method 1 (decimal): 15% = 0.15

0.15 × 64 = £9.60

Method 2 (10% shortcut): 10% of £64 = £6.40

5% = half of that = £3.20

Result: £6.40 + £3.20 = £9.60 tip

The 10% shortcut (divide by 10, then adjust) is faster than a calculator for many common percentages.

Three methods — all give the same answer

  • → Decimal multiplier: Convert % to decimal (÷100), then multiply. 34% of 987 = 0.34 × 987 = 335.58
  • → Fraction method: 34% = 34/100. Then 34/100 × 987 — identical result, different notation
  • → Unitary method: Find 1% first (divide by 100), then multiply by the percentage needed

Mental shortcuts worth knowing

10% = divide by 10. 5% = half of 10%. 1% = divide by 100. 25% = divide by 4. 50% = divide by 2. Combined, these cover most everyday percentages mentally.

Good to know

Understanding percentages of numbers

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Percent means "per hundred"
The word "percent" comes from the Latin per centum — "out of a hundred". So 34% simply means 34 out of every 100. To find a percentage of a number, you convert the percentage to a decimal (divide by 100) and multiply. That's all there is to it.
34% = 34 ÷ 100 = 0.34
34% of 987 = 0.34 × 987 = 335.58
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The fraction method
You can also write the percentage as a fraction: 34% = 34/100. Then multiply: 34/100 × 987. This is identical to the decimal method — just a different notation. For "nice" percentages like 25% = 1/4, the fraction form can be quicker to do mentally (987 ÷ 4 = 246.75).
25% of 987 = 987 ÷ 4 = 246.75
50% of 987 = 987 ÷ 2 = 493.5
10% of 987 = 987 ÷ 10 = 98.7
1% of 987 = 987 ÷ 100 = 9.87