Quick guide
How to use this calculator
- Set A's columns equal to B's rows.
- Enter every value in A and B.
- Read the exact product AB; reversing the matrices can give a different result.
Calculation method
Take row-column dot products
The entry in row i and column j of AB is the sum of products between row i of A and column j of B.
Worked example
Multiply a row by a column
For A = [[1,2],[3,4]] and B = [[2,0],[1,2]], calculate four row-column dot products.
AB = [[4,4],[10,8]]
Supported inputs
Precision and limits
Matrix size
Each input matrix may contain 1–6 rows and 1–6 columns.
Entry precision
Each signed decimal may contain up to 30 digits and 15 decimal places.
Exactness
Finite decimals are converted to reduced fractions before calculation; matrix arithmetic is not rounded.