How to use it
Type an expression with your keyboard or tap the keypad. = or Enter calculates it. C clears everything and ⌫ deletes the last character.
Example: (58000+12%) ÷ 3 — write (58000+58000*12%) / 3
- × ÷ − on the keypad are converted to the standard operators automatically.
- A number followed by % means “divided by 100”, so 50% is 0.5.
- ^ is a power and is right-associative: 2^3^2 is 2^(3^2) = 512.
Supported functions
- sqrt square root, ^ powers, exp eˣ
- sin cos tan and inverses asin acos atan — in degrees (DEG) or radians (RAD)
- log base-10 logarithm, ln natural logarithm
- abs absolute value, constants π (pi) and e
Division by zero, the square root of a negative number and undefined values like tan(90°) report an error instead of a wrong number.
Tips
- For a quick percentage, multiply directly: 20% of 58000 is 20%*58000.
- Use parentheses to control the order: (2+3)*4 is 20, while 2+3*4 is 14.
- Very large or tiny results switch to exponential notation automatically.
Standards and sources
- Arithmetic follows the standard order of operations; trigonometric reference values follow the SI definition of angle measure
- Evaluated locally in your browser with an original expression parser — no external math library
Last reviewed October 7, 2026
Frequently asked questions
How do I use degrees or radians?
Pick DEG for degrees (the usual school mode) or RAD for radians above the keypad. It only affects sin, cos, tan and their inverses.
What does % mean here?
A number followed by % is divided by 100. For example, 50% is 0.5. To find X% of Y, use the percentage calculator or multiply directly, like 20%*58000.
Why does tan(90) fail?
tan(90°) is mathematically undefined (it grows without bound), so the calculator reports an error instead of a misleading number.
Is my calculation sent anywhere?
No. Everything is evaluated in your browser with JavaScript, and nothing is sent to a server or stored.