HEALTH & EVERYDAY
Sleep cycle calculator
Estimate bedtimes from wake time and 90-minute cycles.
Estimated result
23:15
- Sleep duration
- 7.5 hours
Sleep cycles are not exactly 90 minutes for everyone.
SOURCES & REVIEW
Checked against official guidance
Last checked 14 July 2026 · Rule version GB-2026.27.1
NHS: Healthy weight ↗COMMON QUESTIONS
Frequently asked questions
Is this an exact quote or tax return?
No. It is an estimate based on the inputs and assumptions shown.
When was this checked?
The method and linked official guidance were reviewed for the current UK release.