Percentage Calculator
Four percentage problems in one place: what is X% of Y, X is what percent of Y, percentage increase or decrease, and the percent change between two numbers.
How to use the Percentage Calculator
- Choose the mode that matches your question — percent of, percent change, or what percent.
- Type the two numbers into the fields.
- The answer updates as you type; copy it with one tap.
About the Percentage Calculator
Percentage questions look simple until you have to decide which of the four forms you actually need — and mixing up percentage change with percentage points is one of the most common everyday maths mistakes. Each mode here is labelled in plain language so you pick the sentence that matches your problem rather than remembering a formula. Typical uses are exam marks, salary rises, sale prices, and comparing this month's figures with last month's.
Please note: this is an educational estimator. It does not account for processing fees, insurance bundling, prepayment penalties, floating-rate resets or local tax rules, so the figure on a real agreement will differ. Use it to compare options, then confirm with your lender or a licensed financial adviser. Full disclaimer.
Frequently asked questions
How do I calculate a percentage increase?
Subtract the old value from the new value, divide by the old value, then multiply by 100. Use the increase/decrease mode above and it does this for you.
How do I find what percentage one number is of another?
Divide the part by the whole and multiply by 100 — for example 45 out of 60 is 75%. Use the 'X is what percent of Y' mode.
What is the difference between percent change and percentage points?
Percent change is relative to the starting value; percentage points are a plain subtraction between two percentages. Going from 20% to 25% is a 5 percentage point rise but a 25% increase.
Can I use it to work out a discount?
Yes. Use the percent-of mode for a straight discount off a price, and the change mode to see what percentage a price dropped by. The increase and decrease modes handle markups and reductions the same way.
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