Education 2 min read

How to Calculate Percentage Increase (Formula + Examples)

Percentage increase tells you how much a value has grown relative to its starting point. It shows up everywhere — salary raises, price changes, website traffic, investment returns — and the formula is simpler than most people remember.

The formula

Percentage increase = (New value − Original value) ÷ Original value × 100

Three steps:

  1. Subtract the original value from the new value.
  2. Divide that difference by the original value.
  3. Multiply by 100 to get a percentage.

If the result is negative, you have a percentage decrease.

Prefer to skip the math? Our free Percentage Calculator handles increase, decrease and “X is what percent of Y” instantly.

Worked examples

Example 1: Price increase

A subscription goes from $12 to $15 per month.

  • Difference: 15 − 12 = 3
  • Divide by original: 3 ÷ 12 = 0.25
  • Multiply by 100: 25% increase

Example 2: Salary raise

Your salary rises from $52,000 to $58,500.

  • Difference: 58,500 − 52,000 = 6,500
  • 6,500 ÷ 52,000 = 0.125
  • 12.5% raise

Example 3: Website traffic

Traffic grows from 8,400 to 21,000 visits per month.

  • Difference: 21,000 − 8,400 = 12,600
  • 12,600 ÷ 8,400 = 1.5
  • 150% increase — yes, percentage increases can exceed 100%

The most common mistake

People often divide by the new value instead of the original. Going from 100 to 150 is a 50% increase (50 ÷ 100), not 33%. The denominator is always the value you started from.

The reverse matters too: a 50% increase followed by a 50% decrease does not get you back to the start. 100 → 150 → 75. Percentages are always relative to their own base.

Percentage increase vs. percentage points

If a conversion rate goes from 2% to 3%, that’s:

  • an increase of 1 percentage point, and
  • a 50% relative increase

Marketers and journalists mix these up constantly. When a number is already a percentage, be explicit about which one you mean.

Quick reference

ChangePercentage increase
100 → 11010%
100 → 12525%
100 → 15050%
100 → 200100%
100 → 300200%

For any other numbers, the Percentage Calculator gives you the answer instantly — and if you’re working with money over time, the Compound Interest Calculator shows how repeated percentage growth stacks up.

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