Sleep Cycle Calculator - Optimize Your Bedtime & Wake Time

Sleep Cycle Calculator

Calculate bedtimes and wake times aligned to 90‑minute sleep cycles with an adjustable fall‑asleep buffer (default 15 minutes).

Plan

Wake-up time

Minutes to fall asleep

Sleep cycle length (minutes)

Number of cycles to target

4 cycles (≈6h)

5 cycles (≈7.5h)

6 cycles (≈9h)

Tip: Many adults feel best at 5–6 cycles

Assumes cycles average 90 minutes and falling asleep takes about 15 minutes; adjust to match personal patterns.

Enter a time and press Calculate.

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