90分の睡眠サイクルに合わせた最適な就寝・起床時刻を、入眠までの時間も含めて算出。おすすめの昼寝時間も提案します。
| サイクル数 | 時刻 | 合計睡眠時間 |
|---|
| 仮眠タイプ | 長さ | 得られる効果 |
|---|---|---|
| パワーナップ | 10–20 min | すっきり目覚められ、寝ぼけなし |
| リカバリー仮眠 | 30 min | 多少の寝ぼけはあるが、より休息が取れる |
| 深睡眠仮眠 | 60 min | 記憶力アップ、寝ぼけが約10分続く |
| フルサイクル仮眠 | 90 min | レム睡眠1サイクル分、寝ぼけなし |
睡眠は約90分周期(浅い眠り→深い眠り→レム睡眠)で進みます。サイクルの終わりに目覚めるとすっきり起きられますが、サイクルの途中(特に深い眠りの最中)に起きると寝ぼけの原因になります。
起床時刻を指定した場合は、そこから4・5・6・7サイクル分を差し引き、入眠までの時間を加算して逆算します。就寝時刻を指定した場合は、入眠時間の後にサイクルを積み上げて計算します。
Sleep is modelled as whole repetitions of a fixed cycle length. In the wake-time mode the tool subtracts n × cycle plus your fall-asleep latency from the target; in the two bedtime modes it adds latency first and then n × cycle. It evaluates n = 6, 5, 4 and 3, listing all four with their total hours and highlighting the 5-cycle row as the headline answer. Defaults are a 90-minute cycle and 15 minutes of latency.
Cycle length is the input people should change and rarely do. It accepts 60 to 120 minutes in five-minute steps, and its own help note offers 90 for adults, 60 for children and 80–100 for adults who run long or short. Fall-asleep latency accepts 0 to 60 minutes and shifts every result by that amount — if you routinely lie awake half an hour, leaving it at 15 puts each suggested bedtime thirty minutes too late.
Treat the output as rough targets rather than appointments. Ninety minutes is a population average that also drifts across the night, with early cycles shorter and later REM-heavy ones longer, so real boundaries wander away from any exact multiple. Nothing here models sleep debt, chronotype, caffeine, alcohol or night-time wake-ups, and the bed-now option reads your device clock, assuming you begin falling asleep at this moment.
That is the premise this tool encodes: five 90-minute cycles is 7.5 hours and gets highlighted over six. In practice total sleep matters more than boundary alignment, so do not trade away real sleep just to reach a tidier number.
Whatever you genuinely take, not the 15-minute default. The field accepts anything from 0 to 60 minutes and moves every suggested time by exactly that much. If you regularly need 30 minutes, the default leaves each bedtime half an hour too late.
Five cycles at the default 90 minutes is 7.5 hours, the low end of the usual adult range, so that is the row marked as the headline suggestion. Six cycles, a full 9 hours, is still listed if you have the time available.
No. Ninety is an average; individuals commonly run 80 to 100, and cycles lengthen through the night as REM takes a larger share. The Cycle length field accepts 60 to 120 minutes so you can fit a pattern closer to your own.
The reference table gives four options: 10–20 minutes for alertness with no grogginess, 30 minutes for more rest with some sleep inertia, 60 minutes for a memory boost at the cost of roughly 10 groggy minutes, and 90 for one complete cycle.
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