Whoever Says ‘Subhan ALLAHI Wa Bihamdihi’ 100 Times…

Narrated Abu Huraira (may ALLAH be pleased with him):

ALLAH's Apostle (peace and blessings of ALLAH be upon him) said:
Whoever says ‘Subhan ALLAHI Wa Bihamdihi’ (All Glory is to ALLAH and all Praise to HIM) one hundred times a day, will be forgiven all his sins even if they were as much as the foam of the sea.

Reference:
[Sahih Bukhari]