During the 1st of August, Iceland normally records around 17 hours and 51 minutes of total daylight. At the end of the month on the 31st, daylight decreases to 14 hours and 37 minutes, totalling a decline of 3 hours and 14 minutes over the month of August.
Due to Iceland still having many hours of daylight, this summer month is still a great time to take excursions into the Icelandic wilderness, without having to worry about night falling anytime soon.