Mathematics
Scientific Calculator
A full scientific calculator with trigonometry, logarithms, powers, roots and constants.
Privacy
Everything runs in your browser. Nothing you enter is transmitted, logged or stored, and the page keeps working with the network off.
Tips
- Type expressions directly or use the keypad — both feed the same parser, so 2+3*4 correctly gives 14, not 20.
- Supported functions: sin, cos, tan and their inverses and hyperbolics, ln, log, log2, sqrt, cbrt, abs, exp, floor, ceil, round, sign. Use ! for factorial.
- Constants pi, e, tau and phi can be used anywhere a number can.
- The angle mode applies to trigonometric functions only, and is shown next to the display so it cannot be mistaken.
- Expressions are parsed with a proper tokeniser, not eval, so a typo produces a useful message rather than a broken page.
Frequently asked questions
Why does sin(90) give 1 in one mode and 0.894 in another?
Because 90 degrees is a right angle but 90 radians is about 14 full turns. Check the angle mode indicator — it is the most common source of confusion with any scientific calculator.
How precise is it?
It uses double-precision floating point, giving about 15–17 significant digits. That means 0.1 + 0.2 shows as 0.30000000000000004 if you ask for full precision — a property of binary floating point, not a bug.