Sleep Cycle Calculator
Find how many 90-minute sleep cycles you get.
Sleep runs in ~90-minute cycles; waking between cycles feels more refreshing.
The math behind it
cycles = total sleep minutes ÷ 90. Aim to wake at the end of a cycle, not mid-cycle.
Worked example
7.5 h → 5 full cycles.
FAQ
Ideal cycles?
Most adults feel best with 5–6 cycles (~7.5–9 hours).