# Sleep Calculator & Sleep Music

> Free sleep calculator and ambient sleep music — all in one place. Calculate your ideal bedtime and wake-up time based on 90-minute sleep cycles, then fall asleep with curated soundscapes.

Unlike other sleep calculators that only do math, Sleep Calculator & Sleep Music is a complete sleep wellness platform that combines a science-backed sleep cycle calculator with a built-in ambient sound mixer. Users can calculate their sleep schedule and immediately start playing sleep sounds — no need to switch apps.

## Core Tools

- [Sleep Calculator](https://asleepcalculator.app/): Calculate ideal bedtime or wake-up time based on 90-minute sleep cycles. Factors in 15 minutes to fall asleep.
- [Ambient Sleep Music](https://asleepcalculator.app/sleep-music/): Mix ocean waves, rainfall, white noise, and piano melodies. Includes wake-up alarm, moon mode, and scene backgrounds.
- [Nap Calculator](https://asleepcalculator.app/nap-calculator/): Plan 20-min power naps, 40-min cognitive recharges, or 90-min full sleep cycles with a built-in timer.
- [Caffeine Calculator](https://asleepcalculator.app/caffeine-sleep-calculator/): Track caffeine half-life (5.7h) across 6 drink types. See when to stop drinking coffee for better sleep.
- [Breathing Exercises](https://asleepcalculator.app/sleep-breathing-exercises/): Guided 4-7-8, Box Breathing, and Calm Breathing with visual circle animation and audio cues.
- [Sleep Tracker](https://asleepcalculator.app/sleep-tracker/): Enter your sleep and wake times to analyze rest quality, complete cycles, estimated sleep stages, and get a sleep score.

## Specialized Guides

- [Sleep Calculator for Kids](https://asleepcalculator.app/sleep-calculator-for-kids/): Age-specific sleep recommendations for newborns through teens, with bedtime calculator and sleep tips per age group.
- [Sleep Calculator for Women](https://asleepcalculator.app/sleep-calculator-for-women/): How menstrual cycles, pregnancy, and menopause affect sleep — with tailored advice for each life stage.
- [Sleep Science](https://asleepcalculator.app/sleep-science/): How 90-minute sleep cycles work — light sleep, deep sleep, and REM stages explained.
- [Sleep Needs by Age](https://asleepcalculator.app/sleep-needs-by-age/): Recommended sleep hours from newborns (14-17h) to seniors (7-8h).

## Key Facts

- All calculations run client-side — no data sent to servers
- 90-minute sleep cycle model + 15 minutes average sleep onset
- Adults need 5-6 complete cycles (7.5-9 hours) per night
- Caffeine half-life: ~5.7 hours
- Optimal nap window: 1-3 PM

## Optional

- [Privacy Policy](https://asleepcalculator.app/privacy/)
- [Terms of Use](https://asleepcalculator.app/terms/)
- [Cookie Policy](https://asleepcalculator.app/cookies/)