Tell the tool either when you need to wake up or when you plan to fall asleep, and it works out the ideal times using 90 minute sleep cycles. Waking at the end of a cycle, rather than in the middle of deep sleep, tends to leave you feeling more rested even on the same amount of sleep. Counting back from a wake time, it lists several bedtimes that give you four, five or six complete cycles, and counting forward from a sleep time it lists the best moments to set your alarm. It also adds a short buffer for the time it takes to actually drift off. Pick your mode and enter a time to see the suggestions instantly. Everything is computed in your browser with nothing stored.
It uses 90 minute cycles, aiming to have you wake at the end of a cycle rather than in the middle of one.
It allows for the time it takes to drift off, so the suggested bedtimes account for a short period before sleep begins.
It offers a few options spaced 90 minutes apart so you can pick a full number of complete cycles that fits your schedule.
Tell the tool either when you need to wake up or when you plan to fall asleep, and it works out the ideal times using 90 minute sleep cycles. Waking at the end of a cycle, rather than in the middle of deep sleep, tends to leave you feeling more rested even on the same amount of sleep.
Yes. Sleep Bedtime Calculator is completely free, with no sign-up and no usage limits.
Yes. Sleep Bedtime Calculator runs in any modern web browser. There is nothing to download or install.
Yes. Sleep Bedtime Calculator runs entirely on your device in your browser, so nothing you enter is uploaded to a server.