Quadratic Equation Calculator
A free, browser-based calculator. Runs entirely in your browser — no sign up, nothing stored.
100% FreeRuns in your browserBasic
Enter Values
Enter your values and press Calculate to see results.
How to use this calculator
- Enter the coefficients a, b and c from ax² + bx + c = 0.
- Press Calculate for the roots.
How it works
The roots are x = (−b ± √(b² − 4ac)) ÷ 2a. The part under the square root (the discriminant) tells you how many real roots there are: positive gives two, zero gives one, negative gives none.
Worked example
x² − 3x + 2 = 0. Discriminant = 1, so x = 2 and x = 1.
Frequently asked questions
What if there are no real roots?
A negative discriminant means the solutions are complex numbers, which this calculator doesn't show.
Related tools
Tip: Enter any known values to calculate the remaining results.
All calculations run in your browser. Your inputs are never saved or transmitted.