Math Expression Evaluator
Evaluate math expressions safely — + - * / % ^, parentheses, functions (sin / sqrt / log…) and constants, with live results and readable errors.
>_ USAGE GUIDE
Type in a math expression — for example (3+5)*2^3 - 100/(4+6) — and the tool evaluates it in real time and shows the result; when something is wrong, it returns a readable error so you can see where the mistake is.
Supported syntax covers the four basic operations + - * /, remainder %, exponent ^, nested parentheses, common functions (sin, cos, tan, sqrt, log, abs, round, and more), and constants such as pi and e. It is more "programmer-friendly" than a typical calculator — paste a whole formula and evaluate it at once.
- Paste the whole expression: with parentheses and exponents, then get the result
- Call functions: use forms like
sqrt(16),sin(pi/2), orlog(100) - Quick-check a value: verify a number while coding or cross-checking data
Evaluation uses a safe recursive-descent parser — never eval or dynamic execution — so any pasted content is only "arithmetic" and cannot run harmful code. Processing happens entirely in your browser.
>_ FAQ
Q1 · How is this different from the calculator built into my OS?
A typical calculator makes you press buttons step by step; this tool accepts one whole expression with parentheses, exponents, and functions and evaluates it at once — handy for programmers who want to check a formula like (a+b)*c end to end. It also returns readable errors (which bracket is unclosed, which function is unknown) that are easier to debug than mistyping on a calculator.
Q2 · What functions and constants are supported?
The usual math functions are available: trig sin/cos/tan, square root sqrt, logarithms log/ln, absolute value abs, and rounding round/floor/ceil; constants include pi and e. See the in-page hints for the exact set — unsupported input produces a readable error instead of silently computing a wrong answer.
Q3 · Why does it emphasize "no eval"? What is the difference?
eval executes whatever string it receives as code; if the input comes from an untrusted source, that can run arbitrary code — a serious security risk. This tool uses a recursive-descent parser that reads the expression as "math syntax" character by character and only recognizes numbers, operators, parentheses, and a whitelist of functions — it cannot execute code, so pasting arbitrary content is safe.
Q4 · How is operator precedence handled? Is it standard math?
Yes, standard: parentheses first, then exponent (^), then multiply/divide/remainder, then add/subtract, left to right at the same level. For example 2+3*4 is 14 (multiply first), (2+3)*4 is 20, and 2^3*2 is 16 (exponent first). When unsure, add parentheses to state intent explicitly.
Q5 · How do I read an error message?
Errors point at the problem in the expression. Common categories: mismatched parentheses (too many or too few), unrecognized content (illegal characters or an unknown function name), and invalid math (such as division by zero or square root of a negative number). Follow the hint to the offending fragment, fix it, and re-evaluate rather than chasing a vague "error".