Cubic Equation Solver
Solve any cubic equation ax³ + bx² + cx + d = 0 using Cardano's method, returning all real roots and any complex conjugate pair.
Inputs explained
- Coefficient a (ax³ + bx² + cx + d = 0) — The coefficient of x³. Cannot be zero.
- Coefficient b — The coefficient of x².
- Coefficient c — The coefficient of x.
- Coefficient d — The constant term.
How to use it
- Fill in the fields above — each input has a hint describing exactly what to enter
- Press Calculate to get your result instantly, right on this page
- Copy the result, save the tool to favorites, or share and embed it anywhere
Understanding the result
Example: x³ − 6x² + 11x − 6 = 0 has the three real roots x = 1, 2, and 3.
Frequently asked questions
What happens if the cubic has only one real root instead of three? The solver still returns that one real root plus the remaining two roots as a complex conjugate pair, since every cubic has exactly three roots counting complex ones.
Does coefficient a need to be nonzero? Yes; if a = 0 the equation is no longer cubic (it becomes quadratic or linear), so this solver requires a nonzero leading coefficient.
Is the Cubic Equation Solver free to use? Yes — it is completely free, with no sign-up, no download and no usage limits. You can use it as often as you need.
Is my data private? Yes. The calculation runs entirely in your browser — the values you enter are never sent to our servers, stored or shared with anyone.
What information do I need? Just the following: Coefficient a (ax³ + bx² + cx + d = 0), Coefficient b, Coefficient c, Coefficient d. Each field includes a hint explaining exactly what to enter.
Can I use it on my phone? Yes — the tool is fully responsive and works on any device, and the same calculator is available in the EasyWorkCalcs mobile app.
Privacy
Everything you enter into the Cubic Equation Solver is processed entirely in your browser. Nothing is uploaded, stored or shared — your data stays on your device.