Sleep Timing Tools

Free calculators for bedtime, wake time, sleep cycles, caffeine cutoff, and nap length. All based on established sleep science, no account needed.

Sleep Cycle Calculator

Enter your wake time and find the optimal bedtimes based on complete 90-minute sleep cycles.

Bedtime Calculator

Age-adjusted bedtime recommendations. Find when to sleep based on when you need to wake up.

Wake Up Time Calculator

Enter your bedtime and find the best alarm times, timed to the end of a complete sleep cycle.

Caffeine Cutoff Calculator

Find the latest safe time to drink coffee based on caffeine half-life and your metabolic sensitivity.

Nap Duration Calculator

How long should you nap? Get the right nap length for your goal, alertness, memory, or recovery.

Other calculator clusters:

Not medical advice. For sleep disorders, consult a healthcare provider.