➗ Math
Quadratic Equation Calculator
The quadratic formula always works, and the discriminant tells you what to expect before you calculate: a positive value gives two real roots, zero gives one repeated root, and a negative value gives no real roots.
How it works
Coefficient a
Coefficient b
Constant c
Discriminant
First root
Second root
Vertex x
Vertex y
Sum of roots
Frequently asked questions
How do I use the Quadratic Equation Calculator?
Fill in the fields above — the result recalculates instantly as you type. Everything runs in your browser, so the values you enter are never collected or stored.
Is this calculator free?
Yes. It is completely free, requires no account, and works on phones, tablets and desktops.