Returns the matrix product of two arrays. The result is an array with the same number of rows as array1 and the same number of columns as array2.
Syntax
MMULT(array1,array2)
Argument 
Description 
Remarks 
array1,array2 
The arrays that you want to multiply. 
 The number of columns in array1 must be the same as the number of rows in array2, and both arrays must contain only numbers.
 The array1 argument and array2 can be given as cell ranges, array constants, or references.
 If any cells in array are empty or contain text, this function returns the #VALUE! error value.
 If the number of columns in array1 is different from the number of rows in array2, MMULT returns the #VALUE! error value.

General remarks
 The matrix product array a of two arrays b and c is:
 Formulas that return arrays must be entered as array formulas.
Example 1: Returning the matrix product of two arrays
To make the following example easier to understand, you can copy the data to a blank sheet and then enter the function underneath the data. Do not select the row or column headings (1, 2, 3... A, B, C...) when you copy the sample data to a blank sheet.
Note The formula in the example must be entered as an array formula. First, type the formula into cell A8 and then press RETURN . The single result is 2. Next, select the range A8:B9, press CONTROL + U , and then press + RETURN . The array results, from left to right and top to bottom, are 2, 6, 14, and 4.
Array 1 
Array 1 
1 
3 
7 
2 
Array 2 
Array 2 
2 
0 
0 
2 
Formula 

=MMULT(A2:B3,A5:B6) 



Example 2: Returning the matrix product of two arrays
To make the following example easier to understand, you can copy the data to a blank sheet and then enter the function underneath the data. Do not select the row or column headings (1, 2, 3... A, B, C...) when you copy the sample data to a blank sheet.
Note The formula in the example must be entered as an array formula. First, type the formula into cell A8 and then press RETURN . The single result is 6. Next, select the range A8:B9, press CONTROL + U , and then press + RETURN . The array results, from left to right and top to bottom, are 6, 0, 4, and 0.
Array 1 
Array 1 
3 
0 
2 
0 
Array 2 
Array 2 
2 
0 
0 
2 
Formula 

=MMULT(A2:B3,A5:B6) 



See also
MDETERM function
MINVERSE function
TRANSPOSE function
List of all functions (by category)