Percentage Change Calculator — Percent Increase or Decrease Between Two Numbers

How to use the percentage change calculator

1. Enter the Original value, the starting number.
2. Enter the New value, the number it changed to.
3. Read the Increase or Decrease in percent.
4. Check the Difference, the Multiplier (new ÷ old) and the Change needed to return to the original.
5. The Working line shows the formula with your numbers, which you can copy into a report.

What it does and when to use it

Percentage change is how we compare growth and decline fairly. A rise of 60 means a lot for something that started at 250, and very little for something that started at 25,000. Turning the change into a percentage puts both on the same scale.

Common uses:

• Prices. How much has a product, a rent or a fare gone up?
• Pay. What percentage raise did you get?
• Business results. How did sales, visitors or sign-ups change from last month?
• Investments. How much has a share price or a portfolio gained or lost?
• School and sport. How much did a score or a personal best improve?

The extra outputs help you avoid two common traps. The multiplier makes it easy to apply the same change to another number. The recovery figure shows how much harder it is to climb back after a fall. For other kinds of percentage problems, such as finding a percent of a number or removing tax, use the Advanced Percentage Calculator. To work with fractions, try the Fraction Calculator. For averages across many values, see Mean, Median and Mode.

How it works

With original value O and new value N:

• Percentage change = (N − O) ÷ |O| × 100
• Difference = N − O
• Multiplier = N ÷ O
• Change needed to return = (O − N) ÷ |N| × 100

The tool uses exact fractions, so long repeating results are shown with an ellipsis rather than rounded off early. It runs in your browser.

Worked examples

Growth from 80 to 100. (100 − 80) ÷ 80 × 100 = Increase: 25%. The difference is 20 and the multiplier is 1.25. To fall back to 80, the value would need to drop 20%.

A fall from 100 to 75. The result is Decrease: 25%, a difference of −25. Getting back to 100 needs a rise of 33.33%, shown as 33.3333333333…%. Falls always need a bigger percentage rise to recover.

A rent rising from 250 to 310. That is an increase of 24% and a multiplier of 1.24. If a second rent of 400 rose by the same proportion, it would become 400 × 1.24 = 496.

Limits and tips

• Always be clear about which number is the original. Swapping them changes the answer: 80 to 100 is +25%, but 100 to 80 is −20%.
• When the values are themselves percentages, such as interest rates, you may want the change in percentage points instead. The Advanced Percentage Calculator shows both.
• For several changes in a row, multiply the multipliers rather than adding the percentages.