Web Calculator
Web Calculator — runs in your browser. Inputs are not stored.
Web calculator
Enter values, then press Calculate.
Allowed: numbers, + − * / % ( ), some Math.*. e.g. Math.pow(2,10), Math.PI*2
How to use
- Enter the expression in the Expression field. The default example is
2*(3+4). - Press Calculate or Enter to see the result.
- Only numbers, arithmetic, parentheses, percent (%), and Math functions are allowed. Other characters produce an error.
- For powers, roots, and trigonometry, prefix with Math., as in
Math.powandMath.sqrt. - If needed, Reset restores the default expression. Calculation runs only in this device’s browser.
Key concepts
The online web calculator does not execute the input string as-is; it evaluates only allowed subexpressions. Numbers and operators (+ − * / %), parentheses, scientific notation (e), and a fixed set of Math functions pass. Arbitrary variables, browser APIs, and script injection are blocked. Special multiply, divide, and minus signs are rewritten internally to *, /, and -. Parenthesis precedence matches ordinary arithmetic; consecutive operators or empty parentheses are expression errors. As in the hint examples, you can mix powers and pi on one line.
Available functions are abs, sqrt, pow, sin, cos, tan, log, log10, exp, floor, ceil, round, min, max and constants PI, E, LN2, LN10. Trigonometry arguments are radians. Expressions are not sent to a server. For memory, angle mode, or graphs, use a scientific calculator. Log is split into natural and common log, so do not mix up the arguments. If the result is not a finite number, the result field stays empty and only an error message remains.
Example
The default 2*(3+4) is 14. Math.pow(2,10) is 1024, Math.sqrt(16) is 4, and Math.PI*2 is about 6.283. For discount or VAT ratios only, a percent calculator is more intuitive; put length and power numbers in the matching unit converters. For example Math.floor(3.9) is 3 and Math.ceil(3.1) is 4. Math.max(2,8,5) is 8. Leave complex unit conversion to a dedicated converter to make fewer mistakes.
Related: Length converter · Percent calculator · Power converter
Frequently asked questions
Which Math functions can I use in the web calculator?
It supports abs, sqrt, pow, sin, cos, tan, log, log10, exp, floor, ceil, round, min, max and PI, E, LN2, LN10. A Math. prefix is required. Omitting the function name causes an identifier error. Do not write PI alone; write Math.PI.
Is an online calculator expression sent to a server?
No. Calculation runs only in the browser and the expression is not stored or sent. Closing the page also clears the input. The Calculate button and Enter call the same function. Pasting a private expression does not leave it on this page’s server.
How does percent % work in the web calculator?
It is the same % as JavaScript remainder. For “what percent of an amount” discount math, a percent calculator is safer. If you need ratio wording such as 10 percent off, the percent calculator is closer to sentence-style input.
Are trigonometry units radians or degrees?
Radians. To enter 90 degrees, convert as in <code>Math.PI/2</code>. There is no degree-mode switch. Without an angle mode, pasting degree homework as-is gives the wrong value. Convert to radians first.
How does a scientific calculator differ from the web calculator?
This screen focuses on one-line expressions and allowed Math functions. Use a scientific calculator for angle mode, memory, and graphs. There are no graphs, matrices, or complex numbers. It only covers one-line real arithmetic and allowed Math calls.
Do both Calculate and Enter work?
Yes. Pressing Enter in the expression field is the same as Calculate. Reset restores the default sample expression. After reset, the result area is hidden. Press Calculate once more to compute again.
Last reviewed: 2026-09-04