FOIL Calculator

Multiply (ax + b)(cx + d) using the FOIL method.

This tool is for informational and educational purposes only. It is not a substitute for professional financial, medical, legal, or engineering advice. See Terms of Service.

Can't find what you need?

Request a Tool

How to Use the FOIL Calculator

This tool multiplies two binomials using the FOIL method and shows the expanded result.

  1. Enter coefficients. Provide a, b, c, and d for (ax + b)(cx + d).
  2. View the result. The expanded polynomial and the individual FOIL terms appear instantly.
  3. Copy or share. Use the buttons to save or share the result.

About the FOIL Method

FOIL stands for First, Outer, Inner, Last. It is a mnemonic for multiplying two binomials: multiply the First terms (a*c), the Outer terms (a*d), the Inner terms (b*c), and the Last terms (b*d), then add them together. The result is a trinomial: (a*c)x^2 + (a*d + b*c)x + (b*d). FOIL is one of the first algebraic techniques students learn and is the reverse of factoring.

Frequently Asked Questions

What does FOIL stand for?

FOIL stands for First, Outer, Inner, Last. It describes the order in which you multiply terms of two binomials.

Does FOIL work for polynomials with more than two terms?

FOIL is specifically for multiplying two binomials. For larger polynomials, use the distributive property or polynomial multiplication methods.

Is FOIL the reverse of factoring?

Yes. FOIL expands two binomials into a polynomial. Factoring does the reverse, breaking a polynomial back into binomial factors.