Two questions, one calculator
"What is 15% of 200?" and "What percent of 200 is 15?" look similar but ask different things, and mixing them up is one of the most common small math mistakes people make — whether working out a tip, a sales tax, a discount, or how close you are to a savings goal. This tool answers both from the same two numbers, so you don't need to remember which formula goes which way.
The math behind it
| Question | Formula |
|---|---|
| What is X% of Y? | (X ÷ 100) × Y |
| X is what percent of Y? | (X ÷ Y) × 100 |
A common real-world use: a $200 jacket with a 15% discount saves $30, bringing the price to $170 — that's the first formula. If instead you saved $30 and want to know what percentage that was of the original $200 price, that's the second formula, and it comes out to the same 15%.