Matrix Multiplication Calculator
Multiply two compatible matrices with visible dimensions.
How the matrix multiplication calculator works
Matrix multiplication combines rows from the first matrix with columns from the second. Each output cell is a dot product, so the number of columns in A must equal the number of rows in B. This calculator validates both rectangular inputs, reports their dimensions, and computes the complete product without silently padding missing cells or changing row order.
The default matrices are 1, 2 over 3, 4 and 5, 6 over 7, 8. The top-left product cell is 1 times 5 plus 2 times 7, which equals 19. Completing all four row-column products gives the verified matrix with rows 19, 22 and 43, 50.
Reading matrix multiplication calculator results privately
Matrix multiplication is not element-by-element multiplication, and reversing A and B generally changes the result. Every row in one textarea must have the same number of entries, separated by spaces or commas. The tool uses decimal floating-point numbers; it does not preserve symbolic variables, fractions, or exact radicals in matrix entries. This matrix multiplication calculator calculation runs entirely in your browser, so the numbers you enter never leave your device.
Frequently Asked Questions
Why are some matrix dimensions incompatible?
A times B requires the column count of A to equal the row count of B. Those matching positions form each dot product.
Does matrix multiplication commute?
Usually not. A times B can differ from B times A, and the reversed multiplication may not even have compatible dimensions.
Is the matrix multiplication calculator private?
Yes. Its inputs and results stay in your browser. Bushe.co does not upload or store the values used in this calculation.
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