😴 Sleep Duration Calculator

Calculate total sleep hours and quality — Free, No Sign-up, Works in Browser

Free Sleep Duration Calculator Online — Calculate total sleep hours and quality

How to Use the Sleep Duration Calculator

Enter your bedtime and wake time to calculate total sleep duration, number of complete 90-minute sleep cycles, and overall sleep quality.

How many hours of sleep do I need?

Adults need 7-9 hours (4-6 complete sleep cycles). Waking at the end of a cycle helps you feel more refreshed.