Set Apple Watch to automatically wake after a nap

keithfrommarietta wrote:

This misses the point of my question. Certainly, I can set a timer. However, I want the watch to detect when I fall asleep exactly and then wake me a certain number of minutes after I actually fall asleep. If I just set a timer for 20 minutes, but it takes me 19 to fall asleep, that's not much of a nap. I want it to wake me 20 minutes after I fall asleep, even if it takes me 25 minutes to fall asleep...

What you want is a sleep-triggered nap timer: "start counting only once I'm actually asleep."

Unfortunately, as of current Apple Watch/watchOS and iPhone sleep features, there is no built-in option that says:

"Detect when I fall asleep, then wake me 20 minutes later."

The watch can estimate when you have fallen asleep using motion, heart rate, and other signals, but Apple's Sleep and Alarm apps do not expose that detection as a trigger for a delayed alarm.

Possible workarounds

Third-party sleep-tracking apps

Some apps attempt to detect sleep onset and can trigger alarms based on sleep state. Examples include:

AutoSleep, Sleep Cycle, Pillow

However, most of these are designed to, Wake you during a light sleep window, Track sleep quality and Estimate sleep onset after the fact.

They generally do not offer a precise "wake me exactly 20 minutes after sleep onset" feature. You would need to check the latest capabilities of each app.

Some sleep apps can wake you within a window (for example, between 20 and 40 minutes from now) when they think you are in lighter sleep. That is the closest mainstream feature available.

Custom automation (advanced)

In theory, if an app exposes real-time sleep detection and supports automations, a custom solution using:

• Apple Shortcuts
• Health data
• Third-party APIs

They could approximate this. But Apple does not currently provide real-time sleep-onset triggers through Shortcuts that are accurate enough for a 20-minute nap alarm.

The practical reality is Consumer wearables are actually not very good at determining the exact minute you fall asleep.

Even when your Apple Watch reports a sleep start time, that is usually an estimate derived from data collected over several minutes.

If you fell asleep at 2:13 PM, the watch might only become confident of that at 2:18 PM or later.

So even if Apple added this feature, a "wake me exactly 20 minutes after I truly fall asleep" alarm would be difficult to make reliably accurate.

If your goal is a 20-minute power nap, many sleep researchers recommend setting a timer for about 30–35 minutes, assuming it typically takes you 10–15 minutes to fall asleep.

"Siri, set an alarm for ...." Or "Siri, set a timer for 20 minutes."

No.

keithfrommarietta wrote:

Thanks for the thorough response. There are some solid workarounds here, which I’ll look into. I’ve also submitted a feature request to Apple to add this function natively. Thanks again!

It's an interesting idea, one I would not have thought of. However, the ability of wearables (like the Apple Watch, Fitbit, etc.) to accurately detect the onset of sleep is a bit uneven. Sometimes it seems fairly precise, but other times can be "off" by 15 or 20 minutes or so. So if you want just a 20 minute nap, I think the precision of the detection of sleep onset would need to be more precise than it is now. Also, there are varying levels of sleep -- REM, Core, Deep ... maybe if this option existed, it could be user selectable, not sure a short nap ever really gets to Deep sleep ever ...

You are welcome

🦉-53