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# Percentage change
- URL: https://www.esheets.io/percentage-change/
- Published: 2025-07-02T20:02:07.000Z
- Updated: 2026-06-21T17:00:14.000Z
- Author: Richard Linnington
- Tags: Maths, Number

We often use percentage change to compare how much something has increased or decreased over time — like the rise in food prices, the drop in fuel costs, or changes in your test scores. It’s a quick way to see how big a change really is, no matter what the original amount was. [Jump to the questions](#practise-now)

## Practise now

Worksheet preview and key skills 

### Worksheet preview

Practise percentage change with this self-marking maths worksheet.

The interactive worksheet below generates questions, gives instant feedback, and lets students record their score.

#### What you’ll practise

- Finding the amount of increase or decrease.
- Dividing the change by the original value.
- Multiplying by 100 to find the percentage change.
- Deciding whether the result is an increase or decrease.

Use the interactive worksheet below, or read the [Topic guide](#topic-guide) for the method and worked example.

Calculate the percentage change and enter your answer in the box provided.   
For **decreases** you may type either a positive or a negative value (e.g. *34* or *\-34*). 

## Topic guide

### What this worksheet practises

This worksheet focuses on calculating the percentage change between two values. This is useful for comparing how much a price has increased, or how much a population has decreased, relative to its original size.

### Key method

To find a percentage change (either an increase or a decrease), you can use a straightforward formula:

**Percentage Change = (Actual Change ÷ Original Amount) × 100**

1. Find the actual change by subtracting the old value from the new value (or vice versa to find the positive difference).
2. Divide this difference by the *original* starting amount.
3. Multiply the result by 100 to convert it into a percentage.

### Worked example

**A pair of shoes originally cost £40\. The price is increased to £50\. Calculate the percentage increase.**

Step 1: Calculate the actual change in price.

£50 − £40 = £10

Step 2: Divide the change by the original amount.

10 ÷ 40 = 0.25

Step 3: Multiply by 100.

0.25 × 100 = 25%

The price has increased by 25%.

### Common mistakes to avoid

The most common mistake is dividing by the new amount instead of the original amount. In the example above, dividing 10 by 50 gives 20%, which is incorrect. Always double-check that your denominator is the starting value.