Percentage Calculator

Calculate percentages in three different ways.

Percentage Calculator

Calculate percentages in three different ways.

Percentage (X)

Of Value (Y)

Calculation Result

The calculated percentage value.

Enter values to calculate

Calculation Details

Input values and formula used.

Tips for using percentages

When presenting growth, always include the base number. “50% growth” means different things from 2→3 vs 1000→1500.
Percentage points are different from percent change. Going from 5% to 10% is a 5 percentage point increase, but 100% growth.

What Is a Percentage Calculator

A percentage calculator is a tool that solves the three most common percentage problems: finding a percentage of a number, calculating the percentage change between two values, and determining what percentage one number is of another. Instead of remembering formulas or doing mental math, you enter your values and get an instant answer with the formula shown.

This calculator is designed for speed. Whether you are calculating a discount, measuring growth between two periods, or figuring out what share of a total a specific number represents, you get the result immediately along with the exact formula used so you can verify or replicate the calculation.

Common Percentage Calculations in Marketing

Marketers use percentage calculations constantly. Conversion rate is the percentage of visitors who take a desired action. Click-through rate is clicks divided by impressions, expressed as a percentage. Month-over-month growth measures the percentage change from one period to the next. Budget allocation often requires knowing what percentage of total spend goes to each channel.

The percentage change calculation is especially important for reporting. Telling a stakeholder that revenue went from $80K to $120K is less impactful than saying it grew 50%. This calculator handles that conversion instantly, including correctly identifying whether the change is an increase or decrease.

How to Use This Percentage Calculator

Choose one of the three calculation tabs based on your question. Use "Find %" when you know the percentage and want to find the resulting value, like calculating 20% of 150. Use "Change %" when you have a before and after number and want to know the percentage change. Use "Reverse %" when you know the part and the whole and want to find the percentage.

Enter your numbers in the input fields and the result appears instantly. The calculation details panel shows the exact formula used and the input values, which is useful for double-checking your work or explaining the math to someone else. Copy the result with one click.

Understanding Percentage Change vs Percentage Difference

Percentage change measures how much a value has increased or decreased relative to its original amount. The formula is ((new - old) / |old|) * 100. This is directional: going from 100 to 150 is a 50% increase, while going from 150 to 100 is a 33.3% decrease. The base number matters.

Percentage difference, on the other hand, measures the relative difference between two values without implying direction. It uses the average of the two values as the base. This distinction matters in reporting. Use percentage change when you have a clear before-and-after relationship, and percentage difference when comparing two independent values.

Frequently Asked Questions

How do I calculate percentage increase?

Use the formula: ((new value - old value) / old value) * 100. For example, if sales went from 200 to 250, the percentage increase is ((250 - 200) / 200) * 100 = 25%. You can use the Change % tab in this calculator to compute this instantly.

What is the formula for percentage change?

The formula is ((new value - old value) / |old value|) * 100. The absolute value in the denominator handles cases where the original value is negative. A positive result means an increase, and a negative result means a decrease.

How do I find what percentage one number is of another?

Divide the part by the whole and multiply by 100. For example, if 30 out of 120 users converted, the conversion rate is (30 / 120) * 100 = 25%. Use the Reverse % tab to calculate this automatically.

What is the difference between percentage and percentage points?

A percentage point is an absolute difference between two percentages. If your conversion rate goes from 5% to 10%, that is a 5 percentage point increase but a 100% relative increase. Confusing the two is a common mistake in reporting that can significantly misrepresent results.

How do I calculate discount percentages?

To find the discounted price, use the Find % tab. Enter the discount percentage and the original price. Subtract the result from the original price to get the sale price. For example, 20% of $80 is $16, so the discounted price is $64.

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Percentage Calculator

Calculate percentages in three different ways.