Free Math & Statistics Calculators & Tools
Free math calculators for algebra, geometry, probability, statistics, and calculus. Solve equations, graph functions, and explore formulas in your browser.
Pick a math calculator by problem
Use the tool that matches the structure of the problem. The pages below expose the formula or method so you can compare the result with your own setup.
- Quadratic equation solver
Solve ax² + bx + c = 0 and inspect the discriminant, formula substitution, and roots.
- Online graphing calculator
Plot one-variable expressions over a chosen x range on a 2D coordinate plane.
- System of equations solver
Solve 2x2 or 3x3 linear systems and distinguish a unique, inconsistent, or underdetermined result.
- Linear regression calculator
Fit y = mx + b to paired data and review slope, intercept, correlation, and R².
- Riemann sum calculator
Visualize left, right, or midpoint rectangle sums as an approximation to area under a curve.
A calculator can verify arithmetic, but the correct model and units still come from the problem you are solving.