How to Multiply Matrices in Excel with MMULT

MMULT turns an order and a recipe table into ingredient totals and costs — one spilled formula instead of many.

You will learn to

• Multiply an order row by a recipe table
• Cost every product with one MMULT
• Chain two MMULTs into a single total

How it works

MMULT(array1, array2) returns the matrix product of two ranges. The number of columns in the first must equal the number of rows in the second, and the result has the rows of the first and the columns of the second. In Excel 365 the result spills automatically.

A practical way to read it: each result cell is a SUMPRODUCT of one row of array1 with one column of array2. A 1×4 order row times a 4×3 recipe table gives 1×3 ingredient totals; a 4×3 recipe table times a 3×1 price column gives the cost of each product. MMULTs can be nested to go from order straight to cost.

=MMULT(B8:E8,B2:D5)