Math Calculators
Quadratic Formula Calculator
Solve any quadratic equation.
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About the Quadratic Formula Calculator
Solve any quadratic equation ax² + bx + c = 0 in one step. Enter the coefficients a, b, and c and the calculator returns the roots — real or complex — using the quadratic formula, along with the discriminant that tells you how many real solutions exist. It's a core algebra tool that shows the answer for even the trickiest quadratics.
How to use the Quadratic Formula Calculator
- 01Enter your coefficients a, b, and c.
- 02Read the result instantly — it recalculates as you type.
- 03Adjust the numbers to model different scenarios.
Frequently asked questions
What is the quadratic formula?
x = (−b ± √(b² − 4ac)) ÷ 2a. It solves any quadratic equation ax² + bx + c = 0.
What is the discriminant?
b² − 4ac. If positive there are two real roots; if zero, one; if negative, two complex roots. This tool shows all cases.