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Percentage Calculators
Six calculators in one place. Pick a type, enter your numbers, get your answer instantly.
What is X% of Y?
Find the percentage value of any number.
X is what % of Y?
Find what percentage one number is of another.
Percentage Change
Calculate the % increase or decrease between two values.
Percentage Difference
The relative difference between two values (order doesn't matter).
Reverse Percentage
Find the original value before a percentage change was applied.
Margin & Markup Calculator
Enter cost and selling price to see both margin and markup.
US Economic Data
Track key percentage-based metrics that move markets and wallets.
Fed Funds Rate
Current federal funds rate, historical data, and what it means for borrowing costs.
US Inflation Rate
Latest CPI data, year-over-year inflation, and how it affects purchasing power.
US Money Supply (M2)
M2 money supply growth rate and its relationship to inflation and the economy.
Dollar Purchasing Power
How much a dollar from the past is worth today, adjusted for cumulative inflation.
All Calculators
Dedicated pages with formulas, examples, and FAQs.
Frequently Asked Questions
What is X% of Y?
Multiply Y by X and divide by 100. For example, 15% of 200 = 200 × 15 ÷ 100 = 30. Use the "What is X% of Y?" tab above.
How do I calculate percentage change?
Percentage change = ((New − Old) ÷ Old) × 100. A positive result is an increase; negative is a decrease. Example: from 80 to 100 = ((100 − 80) ÷ 80) × 100 = 25%.
What's the difference between percentage change and percentage difference?
Percentage change has a direction — it goes from an original value to a new one. Percentage difference is symmetric — it compares two values without implying which came first, using their average as the reference.
What is a reverse percentage?
A reverse percentage finds the original value before a percentage was added or removed. If a price is £130 after a 30% increase, the original price was 130 ÷ 1.30 = £100.
What's the difference between margin and markup?
Margin is profit as a percentage of the selling price. Markup is profit as a percentage of the cost price. On the same transaction they always produce different numbers. A 40% markup is only a 28.6% margin.