How to Use This Tool 使用说明

1. Choose your mode: "I want to wake up at..." or "I want to go to sleep at...".
2. Enter the desired time using the time picker.
3. The calculator shows optimal times based on 90-minute sleep cycles (5-6 cycles recommended).
4. It takes about 14 minutes on average to fall asleep, which is factored into the calculation.
5. Select the time that best fits your schedule for optimal rest.

1. 选择模式："我想在...起床"或"我想在...入睡"。
2. 使用时间选择器输入目标时间。
3. 计算器基于 90 分钟睡眠周期显示最佳时间（推荐 5-6 个周期）。
4. 入睡前平均需要约 14 分钟，已计入计算。
5. 选择最适合你作息的时间，获得最佳休息。

Frequently Asked Questions 常见问题

• What is a sleep cycle? — A sleep cycle lasts approximately 90 minutes and consists of stages: light sleep, deep sleep, and REM sleep. Completing full cycles (rather than waking up in the middle of one) helps you feel more refreshed.
• How many cycles do I need? — Most adults need 5-6 complete sleep cycles per night, which equals 7.5 to 9 hours of sleep. The exact number varies by individual.
• Why do I still feel tired after enough sleep? — If you wake up in the middle of a deep sleep stage, you may feel groggy regardless of total sleep time. This calculator aims to help you wake up between cycles for a more refreshed feeling.

• 什么是睡眠周期？ — 一个睡眠周期约 90 分钟，包含浅睡、深睡和 REM 睡眠阶段。完成完整的周期（而非在周期中间醒来）有助于让你感觉更清醒。
• 我需要多少个周期？ — 大多数成人每晚需要 5-6 个完整睡眠周期，即 7.5 到 9 小时。具体数量因人而异。
• 为什么睡够了还是累？ — 如果你在深睡阶段中间醒来，可能仍会感到昏沉，与总睡眠时间无关。此计算器旨在帮助你在周期之间醒来，获得更清爽的感觉。