Adds or multiplies two 2×2 matrices — the most commonly searched matrix size for algebra and computer-science learners.
How it works
Addition combines matching positions directly; multiplication combines each row of the first matrix with each column of the second using the standard dot-product rule.
What this does not include
This covers only 2×2 matrices — larger matrices require the same principles extended to more rows and columns, which this calculator doesn’t handle.
How to use this calculator
- Choose an operation and enter both matrices’ four values each.
A worked example
Adding [[1,2],[3,4]] and [[5,6],[7,8]] element-by-element gives [[6,8],[10,12]].
Multiplying the same two matrices row-by-column gives [[19,22],[43,50]] — a very different result from addition, since matrix multiplication combines rows and columns rather than matching positions.
What the variables mean
| Variable | Meaning |
|---|---|
| Matrix A, Matrix B | The two 2×2 matrices, entered cell by cell |
| Operation | Add or multiply |
Edge cases worth knowing
Matrix multiplication is not commutative — A × B generally doesn’t equal B × A, unlike ordinary number multiplication.
Addition requires matching positions, so a missing cell breaks the calculation — every one of the eight input cells needs a value before either operation can run.
Frequently asked questions
Does matrix multiplication work like regular multiplication?
No — matrix multiplication combines rows and columns using a specific dot-product rule, and unlike regular multiplication, the order generally matters (A×B usually isn’t the same as B×A).
Can any two matrices be added together?
Only matrices of the same size — this calculator specifically handles two 2×2 matrices, which always match.
What’s a real-world use for matrix multiplication?
Representing and combining transformations in computer graphics, solving systems of equations, and many machine-learning computations all rely on matrix multiplication.