About This Tool
The Aureus Percentage Calculator is a free online tool — currently in preview — for working out percentages quickly and seeing exactly how each answer is reached. It covers the three calculations people need most often:
- X% of Y — for example, 15% of 2,450.
- X is what percent of Y — for example, 375 out of 2,500.
- Percentage increase or decrease — from one value to another, such as 200 to 250.
Every result is shown together with its formula, so you can check the working rather than take the number on trust. It is useful for discounts, tips, grades, tax, pay changes, and everyday maths.
This is a small, independent tool provided free of charge, with no accounts and no sign-up. Everything runs locally in your own web browser (see the Privacy page).