Health · Utility calculator
Ideal Sleep Window Calculator
Find bedtime options using 90-minute sleep cycles and your wake-up time.
Instant result
Plain-English why
Copyable takeaway
What this means
The calculator subtracts cycle length plus your estimated time to fall asleep, wrapping around midnight where needed.
Formula used
Bedtime = wake time - (cycles x 90 minutes + time to fall asleep).
Worked example
For a 06:30 wake-up and 14 minutes to fall asleep, 5 cycles means a 22:46 bedtime.
Common questions
Can I use this internationally?
Yes. Currency selectors are display-only unless a tool explicitly says otherwise; no currency conversion is performed.
How exact is the result?
It follows the published Technofatty formula for this tool, but real life can add fees, rules, timing quirks, and context.
Plain-English summary
It is a planning aid, not a sleep diagnosis.
This section translates the result into a short, direct takeaway rather than leaving the page at a bare number.
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