Math Evaluator

Type an expression and the result appears before you finish typing

The input field calls mathjs's evaluate() function on every keystroke, so the result updates live — no Enter press or button click needed unless you want to add the expression to your history. The evaluator handles standard arithmetic, operator precedence, and parenthetical grouping without any configuration. For trig functions, pass the angle in radians: sin(pi/6) and cos(pi/3) are both valid. Logarithms work as log(e) for natural log and log10(100) for base-10. Factorial uses the exclamation mark — 5! — and powers accept either ^ or **. Large results switch automatically to exponential notation; integers are shown without a decimal point.

The six sample expressions and the Calculation History panel

The sample buttons load a working expression directly into the input — Basic Arithmetic, Factorial, Trigonometry, Logarithms, Powers and Roots, and a more involved expression combining sin(pi/4), cos(pi/4), and sqrt(2)/2. These are useful as starting points when you're building a more complex expression and want to test one part of it in isolation. Each expression you evaluate is added to the Calculation History list below the input. Clicking any entry in the list reloads that expression, so you can go back and adjust a previous calculation without retyping it from scratch.