Apple Watch Sleep & Stress Tracking with Cortisol+

Cortisol+ brings available sleep data into the same view as wearable stress and recovery signals. It helps you review your nights and routines. It does not measure next-morning cortisol, identify the cause of a wake-up or determine which sleep stage changed your hormones.

What sleep data comes from Apple Watch?

Apple Health can display estimated time asleep and periods classified as awake, REM, core and deep sleep. Availability depends on your watch, software, settings and wear time. Apple's sleep tracking guide explains setup and how to inspect sleep history. These are wearable estimates, not a clinical sleep study.

How sleep contributes to Cortisol+

The app reads permitted sleep records and uses a sleep-derived factor in its wellness model. Sleep has a 20% base weight before missing-data adjustments and other model modifiers. That weight is a software design choice; it does not mean sleep accounts for 20% of your cortisol production. Read the complete scoring methodology and limitations.

A change in the overall score can reflect several inputs, their freshness and the model's assumptions. Comparing two nights cannot isolate the effect of alcohol, a supplement or a particular sleep stage. We do not promise that a personal hormone pattern will become visible after two or four weeks.

Getting started with sleep tracking

1. Set up sleep tracking and wear a charged, comfortably fitted watch to bed, following Apple's instructions.
2. Check that the night appears in Health before looking for it in Cortisol+.
3. Review the app's Health permissions and choose which available records to share.
4. Note the date of the sleep record and the timestamps of other readings; they may cover different periods.

If sleep or HRV is missing, begin with the source data and permissions. Our missing-data troubleshooting guide explains that decision path for HRV. Enabling read access does not create a measurement that the watch did not record.

Paid creator video · Jizil

A daily sleep and stress tracking routine

Jizil shows sleep-stage views, wearable-derived insights and Zen’s guided breathing. Compare the app’s available sleep records with your own routine and observations; the video does not establish that a sleep change caused a hormone change.

The app interprets wearable data; its cortisol score is an estimate, not a measured hormone level. Biological age is also an estimate. This promotional video is not clinical evidence or an independent review.

Watch this Short on YouTube · Read the methodology

Download on the App Store

Free to download. Analysis requires a subscription or an eligible trial. Playback is provided by YouTube.

Make an observation journal

Use the seven-day stress and sleep journal to record bedtime, wake time, routines and how you felt. Compare those observations with the available records. You can print it or download a blank CSV; the page does not send your entries to analytics.

Can the app explain a 3 AM wake-up?

No. A wake-up time and a wearable score cannot establish its cause. Cortisol+ does not diagnose insomnia, sleep apnea, perimenopause or a cortisol disorder. If sleep problems persist or affect your daily life, discuss them with a healthcare professional instead of relying on the app to choose treatment.

Does a sleep score replace a cortisol test?

No. Medical cortisol testing uses blood, urine or saliva and is interpreted in the context of the test's timing and purpose. MedlinePlus explains cortisol tests. Cortisol+'s score is a separate wellness interpretation of wearable data.

See HRV stress monitoring, our Apple Watch stress guide, and download and subscription information before deciding whether the app fits your needs.