How SolveStep actually solves your math
No mystery black box — here's exactly what happens between typing your problem and seeing the answer.
SolveStep reads what you typed — numbers, the variable x, operators, and parentheses — and builds it into a structured expression tree, the same way a calculator or spreadsheet interprets a formula.
If your input contains an "=" sign, it's treated as an equation and solved algebraically. An inequality sign (< > ≤ ≥) routes to the inequality solver instead. Calculus phrasing like "d/dx" triggers the power-rule engine. Everything else is evaluated as an arithmetic expression — including sin, cos, tan, log, and ln — respecting order of operations.
Rather than jumping straight to a final value, the solver works through the same sequence a person would: reduce parentheses, combine like terms, isolate the variable, or apply the power rule — logging a plain-English description of each move. Where it's possible to double-check the result — a solved equation, a factorable quadratic — SolveStep substitutes the answer back in and shows the check as its own step.
The whole engine is JavaScript that runs locally on your device. Nothing is uploaded to a server, so results appear instantly and your problems stay private.
What SolveStep is — and isn't
SolveStep exactly computes fraction arithmetic (no rounding drift), solves linear and quadratic equations and linear inequalities in one variable, factors quadratics with rational roots, evaluates sin/cos/tan/log/ln numerically, and applies the power rule to polynomial derivatives and integrals of any degree. It's built to be a transparent study aid, not a replacement for understanding the underlying method — the goal is for you to see the method clearly enough to reproduce it yourself.
It currently does not support systems of equations, calculus of trigonometric or logarithmic functions (chain rule, etc.), or multivariable calculus. If a problem falls outside that range, the tool will say so rather than guess.