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Every percentage calculation you'll ever need.

Free, fast, no signup. A professional suite of tools for precise calculations. All on a single page, designed for speed.

What is X% of Y?

Basic percentage calculation

%
Result
0.00
Formula: Result = (X / 100) * Y
History

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X is what % of Y?

Find percentage value

Result
0.00%
Formula: Result = (X / Y) * 100
History

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Percentage Change

Increase or decrease between two values

Result
0.00%
Formula: Result = ((New - Old) / |Old|) * 100
History

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Percentage Increase

Add a percentage to a value

%
Result
0.00
Formula: Result = V * (1 + P / 100)
History

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Percentage Decrease

Subtract a percentage from a value

%
Result
0.00
Formula: Result = V * (1 - P / 100)
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Percentage Difference

Compare two values (neutral direction)

Result
0.00%
Formula: Result = (|V1 - V2| / ((V1 + V2) / 2)) * 100
History

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Reverse Percentage

Find original value before a % was applied

%
If Increase
0.00

V / (1 + P/100)

If Decrease
0.00

V / (1 - P/100)

History

No calculations yet.

How to Use These Percentage Calculators

Percentages are one of the most common mathematical concepts you encounter daily — from sales tax and tips to investment returns and grade calculations. The seven calculators on this page cover every standard percentage scenario you are likely to need.

What Is X% of Y?

Use this when you know a percentage rate and a base number but need the resulting amount. Common uses include calculating tips (15% of a $60 bill = $9), sales tax (8% of a $250 purchase = $20), or commission (5% of $10,000 in sales = $500). Enter the percentage and the base value, and the calculator returns the result instantly with the formula shown.

X Is What Percent of Y?

Use this to find what percentage one number represents of another. For example, if you scored 85 out of 100 on a test, this calculator shows you scored 85%. It works for any part-to-whole relationship: what percentage of your income goes to rent, what portion of a goal you have achieved, or how much of a budget has been spent.

Percentage Change

This calculator measures how much a value has increased or decreased relative to its original amount. Investors use it to track stock performance. Shoppers use it to understand price changes. Businesses use it to measure month-over-month revenue growth. The result shows both the percentage and whether it was an increase or decrease.

Percentage Increase & Percentage Decrease

These two calculators apply a percentage change to a number directly. Use Percentage Increase to add a percentage (e.g., applying a 10% service charge to a bill) and Percentage Decrease to subtract a percentage (e.g., applying a 25% discount to a retail price). They are useful for quick markup and markdown calculations.

Percentage Difference

Unlike percentage change (which is directional), percentage difference compares two values symmetrically using their average as the denominator. This is useful when you want to compare two numbers without designating one as the "original." For instance, comparing prices between two stores or measurements from two different methods.

Reverse Percentage

Use the reverse percentage calculator when you know the final value after a percentage change but need to find the original amount. For example, if a jacket costs $63 after a 30% discount, what was the original price? This calculator handles both increase and decrease scenarios. It is commonly used for finding pre-tax prices, original sale prices, or starting investment amounts.

Tips for Accurate Percentage Calculations

  • Use the right calculator for your scenario. Percentage change is directional (requires an original and new value), while percentage difference is symmetric (no reference point).
  • Check your units. All calculators work with any unit (currency, weight, quantity) as long as both inputs share the same unit.
  • Verify critical calculations. For financial or medical decisions, always double-check results. Each calculator displays its formula so you can verify the math.
  • Understanding 100%. A value of 100% means the whole or total amount. Values above 100% indicate more than the whole, which is common in growth and increase scenarios.

Real-World Uses for Percentage Calculators

Personal Finance

Calculate annual percentage yield on savings accounts, determine how much of a monthly budget goes to housing, or figure out the real interest rate on a loan after fees.

Shopping & Discounts

Compare sale discounts across stores, calculate final prices after stacking coupons, determine sales tax amounts for online purchases from different states or countries.

Academic Grading

Convert test scores to percentages, calculate weighted assignment grades, determine what score is needed on a final exam to achieve a target grade, or convert GPA to a percentage scale.

Business Metrics

Track revenue growth quarter-over-quarter, calculate profit margins on products, measure customer conversion and churn rates, or determine market share relative to competitors.

Health & Fitness

Track weight loss progress as a percentage of starting body weight, calculate body fat percentage, measure calorie deficit relative to maintenance needs, or monitor changes in blood sugar readings.

Real Estate & Property

Calculate down payment percentages, estimate property tax as a percentage of home value, determine rental yield on investment properties, or track property value appreciation over time.

Percentage Calculator FAQ

How do I calculate percentage of a number?

To find what X% of Y is, multiply Y by (X ÷ 100). For example, 20% of 500 = 500 × (20 ÷ 100) = 500 × 0.20 = 100. Use our 'What is X% of Y?' calculator above for instant results.

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

Divide the part by the whole and multiply by 100. To find what percentage 50 is of 200: (50 ÷ 200) × 100 = 25%. Our 'X is what % of Y?' tool handles this instantly.

How do I calculate percentage change between two numbers?

Subtract the original value from the new value, divide by the absolute value of the original, then multiply by 100. If a stock rises from $100 to $120: ((120 - 100) ÷ 100) × 100 = 20% increase. Use our Percentage Change calculator above.

How do I reverse calculate a percentage to find the original value?

If you know the final number after a percentage was applied and want to find the original, divide the final number by (1 + percentage/100) for increases, or (1 - percentage/100) for decreases. Example: a $75 price after 25% off means original = 75 ÷ 0.75 = $100.

What is the difference between percentage increase and percentage difference?

Percentage increase measures change from an old to a new value relative to the old value (directional). Percentage difference compares two values symmetrically using their average as the base — it is not directional. Use Percentage Change for increases/decreases and Percentage Difference for neutral comparison.

When would I use a reverse percentage calculator?

Reverse percentages are useful for finding original prices before tax or discounts, calculating starting investment amounts before gains or losses, and determining base salary before a raise.

How accurate are your percentage calculators?

All calculators display the formula they use, and results are computed client-side to 4 decimal places. You can verify any result by applying the formula manually. Our formulas are cross-referenced against authoritative sources.