Math

2x2 Matrix Multiplication Calculator

Multiply two 2x2 matrices.

Enter your values

Enter the a11 you are working with.

Enter the a12 you are working with.

Enter the a21 you are working with.

Enter the a22 you are working with.

Enter the b11 you are working with.

Enter the b12 you are working with.

Enter the b21 you are working with.

Enter the b22 you are working with.

Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.

Results
A x B
[[4, 6], [1, 3]]
Top-left entry
4
Bottom-right entry
3

Quick answer

Each entry of the product is the dot product of a row of A with a column of B.

(AB)[i][j] = sum_k A[i][k]*B[k][j]

At a glance

What it doesMultiply two 2x2 matrices.
CategoryMath
Inputs neededA11, A12, A21, A22, B11, B12, B21, B22
Main outputA x B
Formula(AB)[i][j] = sum_k A[i][k]*B[k][j]
CostFree — no sign-up, no download

How to use the 2x2 Matrix Multiplication Calculator

  1. 1Enter the entries of matrix A and matrix B in row-major order.
  2. 2The calculator multiplies rows of A by columns of B.
  3. 3Read the resulting 2x2 product matrix.

Inputs explained

A11
Enter the a11 you are working with.
A12
Enter the a12 you are working with.
A21
Enter the a21 you are working with.
A22
Enter the a22 you are working with.
B11
Enter the b11 you are working with.
B12
Enter the b12 you are working with.
B21
Enter the b21 you are working with.
B22
Enter the b22 you are working with.

Worked example

Using the values the calculator loads with:

Inputs

  • A111
  • A122
  • A210
  • A221
  • B112
  • B120
  • B211
  • B223

Results

  • A x B[[4, 6], [1, 3]]
  • Top-left entry4
  • Bottom-right entry3

Frequently asked questions

Is matrix multiplication commutative?

No — AB usually does not equal BA.

Can I multiply matrices of other sizes?

This tool is built for 2x2; the same row-times-column rule extends to other compatible sizes.

What do I need to enter into the 2x2 Matrix Multiplication Calculator?

Just 8 values: a11, a12, a21, a22, b11, b12, b21, b22. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.

How does the 2x2 Matrix Multiplication Calculator work out the answer?

Each entry of the product is the dot product of a row of A with a column of B. It applies the formula (AB)[i][j] = sum_k A[i][k]*B[k][j] and shows the working so you can check each step by hand.

Is the 2x2 Matrix Multiplication Calculator free, and do I need an account?

It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.

Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.