Free FOIL Calculator

How to Use This FOIL Calculator

1. Type your expression into the "Expand" box, with each part in its own parentheses — for example (3x-2)(4x+1). Use a plain - for subtraction and no spaces are required.
2. Squaring a binomial? Enter it with the exponent right after the closing parenthesis, like (x-5)^2, instead of typing the same expression twice.
3. Click Calculate. The expanded, simplified answer appears on the right, along with the full First/Outer/Inner/Last breakdown underneath it.
4. Use Copy, Print or Share to grab the result — Copy puts the plain-text answer on your clipboard, Print gives you a clean printout of just your expression and the steps, and Share generates a link that reloads with your exact numbers and result already filled in.
5. Click Clear to reset the box and start a new expression.

What Is the FOIL Method?

A binomial is just an expression with two terms, like (3x − 2). FOIL is a memory trick for multiplying two binomials together correctly — it stands for First, Outer, Inner, Last, and it's really just the distributive property applied twice.

The FOIL Formula

(a + b)(c + d) = ac + ad + bc + bd

Worked Example

Multiply (3x − 2)(4x + 1):

First: 3x × 4x = 12x²
Outer: 3x × 1 = 3x
Inner: −2 × 4x = −8x
Last: −2 × 1 = −2

12x² + 3x − 8x − 2 = 12x² − 5x − 2

Squaring a Binomial

(x − 5)² means the same thing as (x − 5)(x − 5) — you're just multiplying the binomial by itself, so the exact same FOIL steps apply:

(x − 5)² = x² − 10x + 25

FOIL and the Quadratic Equation

Multiplying two linear binomials with FOIL always produces a "second order" polynomial — one where x² is the highest power — which is exactly what a quadratic equation looks like. Set that result equal to zero and you've got a quadratic equation, solvable with the quadratic formula:

x = (−b ± √(b² − 4ac)) ÷ 2a

Beyond Basic Binomials

"FOIL" technically only describes multiplying two two-term expressions, but the same underlying idea — multiply every term in the first expression by every term in the second, then combine like terms — works for longer expressions too. This calculator handles those automatically, listing every term-by-term product rather than just First/Outer/Inner/Last labels.

Using the Share, Print and Copy Options

• Share: After you calculate, a ready-made link appears with your exact expression baked in. Send it to anyone and their page opens already filled in with your result showing.
• Print: Prints just your expression and the worked steps — no ads, menus or surrounding page clutter.
• Copy: Copies a plain-text version of the answer straight to your clipboard, ready to paste anywhere.

---

Frequently Asked Questions (FAQs)