Math Equation Solver

The Math Equation Solver is a free online tool that evaluate math expressions safely (shunting-yard, no eval), solve linear equations and 2x2 systems, and compute percentage problems with step-by-step solutions.. It runs entirely in your browser with no installation or sign-up needed.

No. The parser uses the Shunting-yard algorithm to tokenize and evaluate safely.

sin, cos, tan, asin, acos, atan, sqrt, cbrt, abs, ceil, floor, round, log, log10, log2, exp, pi, e.

Cramer rule for 2x2 systems. Detects parallel (no solution) and identical lines (infinite solutions).

Yes, the Math Equation Solver is 100% free with no registration, no hidden fees, and no usage limits. All processing happens locally in your browser, ensuring complete privacy.

Absolutely. The Math Equation Solver processes everything client-side in your browser. No data is uploaded to or stored on any server. Your content remains private on your device at all times.

Yes, the Math Equation Solver is fully responsive and works on smartphones and tablets. You can use it on any device with a modern web browser -- no app download required.

No account or registration is needed. Simply open the Math Equation Solver in your browser and start using it immediately. There are no sign-up walls or usage restrictions.

The Math Equation Solver uses industry-standard formulas and algorithms to ensure accurate results. However, for critical financial or medical decisions, always consult a qualified professional.

Simply enter your input in the provided field, adjust any settings to your preference, and the tool will process it instantly. You can then copy the result to your clipboard or download it.

The expression evaluator works in radians, which is the standard for JavaScript and most programming math. So sin(pi/2) returns 1 because pi/2 radians equals 90 degrees, and sin(90) does not give 1 because 90 is read as 90 radians, not degrees. If you have an angle in degrees, convert it first by multiplying by pi/180: for the sine of 30 degrees, enter sin(30 * pi / 180), which returns 0.5. The same rule applies to cos and tan, and the inverse functions asin, acos, and atan return their results in radians too. The constant pi is built in, so you never need to type the digits by hand. Type your full expression into the Expression tab and the tool evaluates it instantly with a token breakdown showing exactly how it read your input.

Open the System of equations tab and enter the six coefficients for the standard form a1x + b1y = c1 and a2x + b2y = c2. For your example you would enter a1=2, b1=3, c1=12 for the first equation, and a2=1, b2=-1, c2=1 for the second. The solver applies Cramer's rule: it computes the determinant of the coefficient matrix, then divides to find x and y, printing each step so you can follow the arithmetic. Here the answer is x=3, y=2. Importantly, if the determinant is zero the tool tells you whether the lines are parallel with no solution or identical with infinitely many solutions, rather than silently failing. Enter your own coefficients to get both the solution and the reasoning.

The Percentage tab handles the three questions people actually run into, each using a different formula. "What is X% of Y?" finds a part from a rate and a whole, so 15% of 80 returns 12. "X is what percent of Y?" finds the rate, so 12 out of 80 returns 15%. And "X is Y% of what?" works backward to find the whole, so 12 being 15% of something returns 80. The confusion usually comes from mixing these up, because the same three numbers play different roles depending on which value is unknown. The tool shows the exact formula it applied for each type, which makes it a quick way to learn the relationship between part, whole, and rate instead of memorizing three separate procedures. Pick the matching question type, enter your numbers, and read both the answer and the formula.

A few common inputs trigger errors by design. Dividing by zero, or using the % modulo operator with a zero on the right, returns a clear "division by zero" or "modulo by zero" message instead of a misleading number. Functions also have valid input ranges: sqrt of a negative number, or asin and acos of a value outside the range -1 to 1, are mathematically undefined and the tool flags them rather than printing NaN. Mismatched or missing parentheses and unrecognized function names will also stop evaluation, since the parser only accepts its known operators and functions. Because it uses the Shunting-yard algorithm rather than eval(), it can point to exactly which token caused the problem. Check your parentheses and argument values, then re-run the expression in the Expression tab to see the corrected result and its token breakdown.

Yes. The Expression tab keeps a running history of your recent results during your session, so you can glance back at earlier calculations without retyping them. Any individual answer, whether an expression value, a solved equation, or a percentage result, can be copied to your clipboard with one click, or downloaded as a plain text file that includes the step-by-step working, not just the final number. That makes it easy to paste a result into a document or spreadsheet, or to keep a record of how an answer was reached for homework or a report. The history lives only in your browser for the current session and clears when you reset it, since nothing is sent to a server. Run your calculations in the relevant tab, then use the copy or download buttons to keep whatever you need.