how do you calculate percentages increase

Quick answer: the formula for percentage increase

If you are wondering, “How do you calculate percentages increase?”, the process is simple once you know the formula.

This tells you how much something changed relative to where it started.

Step-by-step method

1. Find the difference: New Value − Original Value
2. Divide by the original value: Difference ÷ Original Value
3. Convert to percent: Multiply by 100

That’s it. Three steps, and you have your percentage increase.

Example 1: Price increase

A product goes from $50 to $65.

• Difference = 65 − 50 = 15
• 15 ÷ 50 = 0.30
• 0.30 × 100 = 30%

The price increased by 30%.

Example 2: Salary increase

Your salary rises from $40,000 to $46,000.

• Difference = 46,000 − 40,000 = 6,000
• 6,000 ÷ 40,000 = 0.15
• 0.15 × 100 = 15%

Your salary increased by 15%.

Why the original value matters

Percentage change is always based on the starting number, not the new number. This is one of the most common mistakes people make.

For example, if something grows from 20 to 30:

• Difference = 10
• 10 ÷ 20 = 0.5
• Increase = 50%

If you divide by 30 instead, you get the wrong result.

Percentage increase vs. percentage decrease

The same formula can show both increase and decrease.

• If the result is positive, it’s an increase.
• If the result is negative, it’s a decrease.
• If the result is 0, there was no change.

So even though the question is about percentage increase, the calculator above can handle all three cases.

Common mistakes to avoid

• Using the new value as the base instead of the original value.
• Forgetting to multiply by 100 at the end.
• Confusing percentage points with percent change. A move from 10% to 15% is a 5 percentage-point increase, but a 50% relative increase.
• Trying to divide by zero. If the original value is 0, percentage increase is undefined.

How to calculate a new value after a known increase

Sometimes you know the percentage increase and want the final amount. Use this:

Example: Increase 120 by 25%:

• New Value = 120 × (1 + 25/100)
• New Value = 120 × 1.25 = 150

Real-world uses of percentage increase

You’ll use this in daily life more than you might think:

• Budgeting and tracking expenses
• Evaluating investment returns
• Comparing inflation over time
• Analyzing business growth metrics
• Reviewing performance improvements
• Checking discounts and markups

FAQ

Is 100 to 120 a 20% increase?

Yes. Difference is 20. Divide by 100 and multiply by 100, giving 20%.

What if the number went down?

You still use the same formula. The result will be negative, indicating a percentage decrease.

Can percentage increase be more than 100%?

Absolutely. If a value more than doubles, the increase is above 100%.

Final takeaway

To calculate percentages increase, subtract the original value from the new value, divide by the original value, and multiply by 100. Once you practice with a few examples, it becomes second nature. Use the calculator above anytime you need a fast and accurate answer.