Percentage Increase/Decrease Calculator

Find percent change between two values — instantly. Includes difference, direction, and a clean step-by-step breakdown.

📈 Increase / Decrease 🧮 Step-by-step ✅ Rounding options

Values

✅ Inputs

Baseline value (before change).

Value after change.

Choose how many decimals to display.

Signed shows increase/decrease clearly.

Formula: % change = ((new − old) / old) × 100

Step-by-step

Enter values and click Calculate.

Results

🔥 Output

Percent change

Difference (new − old)

Magnitude

Summary

Enter values to see a clean summary.

Explanation

The Percentage Increase/Decrease Calculator measures how much a value changed relative to its starting point. It is commonly used in finance, pricing, business metrics, sales growth, and comparisons like “this month vs last month”.

Tip: If the old value is 0, percent change cannot be computed (division by zero). In that case, use the absolute difference instead.

Formula

Percent change = ((new - old) / old) × 100

FAQs

When is percent change undefined or infinite?

If the old value is 0, percent change is undefined/infinite because you can’t divide by zero.

Sign meaning?

Positive means increase and negative means decrease.

Can it exceed 100%?

Yes. If the new value is more than double the old value, percent increase is greater than 100%.

Is this the same as percentage points?

No. Percentage points are the absolute change between percentages (e.g., 10% to 12% is +2 points).

Rounded result?

For general use, 2 decimals is common. For dashboards, 0–1 decimals may be enough.