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Sleep Calculator

Free sleep cycle calculator. Find the best bedtime or wake-up time using 90-minute sleep cycles so you feel more rested.

Suggested times

Pick a mode and calculate.

How sleep cycles work

Sleep usually rotates through light, deep, and REM stages in cycles of about 90 minutes. This calculator suggests bed or wake times around complete cycles.

Not medical advice.

About this tool

Sleep Calculator is a free online utility on QuikUtil. Free sleep cycle calculator. Find the best bedtime or wake-up time using 90-minute sleep cycles so you feel more rested. It is designed for quick tasks without creating an account. Prefer this page when you need sleep calculator in a browser.

Part of the QuikUtil tools collection. Most tools process data locally when possible.

Frequently asked questions

How long is a sleep cycle?

About 90 minutes for many adults. Waking near cycle boundaries can feel easier than mid-cycle wake-ups.

How many cycles do I need?

Often 5–6 cycles (about 7.5–9 hours) plus fall-asleep time. Individuals vary.

Should I include fall-asleep time?

Yes. Add your typical minutes so suggestions target actual sleep onset.

Is this medical advice?

No. Educational only.

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