Sleep Calculator
Bedtimes or wake-up times aligned with 90-minute sleep cycles.
See how it works
Watch a quick simulation of this tool in action — no file needed.
How to use Sleep Calculator
Follow these steps — everything happens instantly in your browser.
- 1
Step 1. Pick your goal: wake up at a specific time or go to bed now.
- 2
Step 2. Enter your target wake-up or bedtime.
- 3
Step 3. Read 4 options (3–6 cycles) for the opposite end of your sleep.
Why use this tool
Frequently asked questions
Everything you might want to know about sleep calculator.
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