Free · one click · no permissions
Set alarm for 10 AM
The alarm time is preloaded to 10 AM. Click Set alarm and you're done. It shows exactly how long until it rings.
Keep this tab open — the alarm rings from your browser, with a synthesized chime that needs no downloads and no permissions.
To wake at 10 AM, go to bed at
12:45 AM
6 cycles · 9 hours
2:15 AM
5 cycles · 7.5 hours
3:45 AM
4 cycles · 6 hours
Based on 90-minute cycles plus 15 minutes to fall asleep. Real cycles run roughly 70 to 120 minutes and change across the night, so treat these as a better starting point than a guess rather than a schedule to obey.
Waking at 10 AM
A genuinely late start, usually for night shifts or catching up after a short night. Worth pairing with dim light in the evening, since a late wake makes the following night's sleep harder to start.
The sleep calculator works the same maths in the other direction if you want to start from a bedtime, and the alarm clock holds as many alarms as you need.
Frequently asked questions
- How do I set the alarm for 10 AM?
- The time field is preloaded to 10 AM — click Set alarm and it's armed. The card below shows exactly how long until it rings.
- Will the alarm ring if my computer sleeps?
- The tab must be open and the computer awake — a browser can't ring from a sleeping machine. Keep the tab open; the page holds your screen awake while an alarm is armed.
- Do I need to allow notifications?
- No. The chime is synthesized inside the page when you set the alarm, so there's no permission prompt and nothing to install.