The break-even point for Strassen's algorithm is not unrealistic -- it is around the 1000x1000 range. You might be thinking of the best known algorithms: http

The break-even point for Strassen's algorithm is not unrealistic -- it is around the 1000x1000 range. You might be thinking of the best known algorithms: https://en.wikipedia.org/wiki/Coppersmith-Winograd_algorithm https://en.wikipedia.org/wiki/Coppersmith-Winograd_algorithm Strassen's algorithm is certainly used in practice.