What is the limit on array size in a google sheets formula?

Question

I number myself among several people in the Mmultiverse (c) who use two-dimensional arrays in google sheets, typically to produce a rolling total for a set of data - this is a good example.

It looks as though you can have very large arrays in google scripts according to this, but I can't find documentation for their size in a sheet formula: what is the limit (if any), and what impact would this have on the use of Mmult formulas as above?

question from:https://stackoverflow.com/questions/65599541/what-is-the-limit-on-array-size-in-a-google-sheets-formula

Answer 1

10,000,000 (10^7).

The array used in an mmult formula is typically a square array. The impact of the 10 million cell limit on a square 2D array is that you can have sqrt(10^7) rows and the same number of columns. In other words, you can process 3162 rows of data using an mmult technique that produces a square 2D array, but not 3163.

With

=sum(sequence(3162,3162))

With

=sum(sequence(3163,3163))

As noted by @player0, many other combinations of height and width are possible in rectangular arrays from 10m rows X 1 column up to 1 row X 10m columns as long as the total number of cells does not exceed 10m.