wait, my apple watch can tell when i'm stressed?
Pretty much. Your watch already saves your heart rate, sleep, HRV and breathing. Cortisol IQ rolls them into one cortisol score, compared with your own usual, and colours your watch face with it. Green when you're calm. Red when you're running hot.
Coming soon to the App StoreAn estimate from your watch, not a lab test. How it works
me finding out my apple watch could do this the whole time 😭
red in the meeting. green on the train home.
40 means you're right at your usual. The further your signals drift from it, the higher it goes.
Low · under 30
Usual · 30–49
Raised · 50–59
High · 60+
four things, one watch.
Your score, at a glance
Add the complication and your score sits next to the time. Or fill the whole watch screen with its colour.
Calm-day goals
Choose how many calm days a week you're after, from 2 to 7. Your watch keeps count.
Kai, your AI coach
Ask why you're up today and what to try. Kai knows your numbers.
Sleep that counts
Last night sets this morning's starting point. The Sleep tab shows how long you slept and in which stages.
one number, and the readings behind it.
Your score, its band, your signals beside your usual, and how old the readings are. One glance tells you whether today is an ordinary day for you.
a quick look around.
Home on your watch
Your score in its colour, with your HRV and resting heart rate underneath. Kai's face changes with it.
Why you're at 55
Tap the score to see how many points each signal adds or takes off.
Your day
Every hour with a reading, and today's peak marked.
Last night
Time asleep and sleep stages, straight from your watch.
One-minute breather
Breathe along on your watch and see your heart rate before and after.
Kai, the AI coach
Ask Kai what's up with your numbers and get a short, plain reply.
it works the first time you open it.
No first-scan loop, no week of waiting, no refresh button to babysit.
Your usual is already there
Your usual is learned from the last 4 weeks in Apple Health. If there's a week of readings, you won't wait.
Updates without you
When your watch saves a new reading, your score updates in the background.
Missing data never pushes it up
A missing signal counts for less and your score leans toward your usual. You'll see "rough estimate" and what would help.
Says when data's old
Watch off your wrist for hours? You'll see "No new readings since 9:14".
every point explained.
Tap your score and see exactly how many points each signal adds or takes off. They add up to your number. Same readings, same score, any hour.
- At your usual
- 40
- Resting heart rate 60, usual 56
- +6
- Overnight HRV 41 ms, usual 48
- +5
- Heart rate while sitting
- +3
- Sleep 6h 30m
- +1
- Your score
- 55
a nudge when it counts. then quiet.
A tracker that buzzes all day just adds stress. So alerts are rare on purpose.
- About an hour, not a blipYour watch taps you only when your score has stayed above your alert level for about an hour.
- Your lineYour alert level starts at 60. Move it whenever you like.
- Two a day, topsAt most two in 24 hours, at least three hours apart, never overnight.
- Workouts don't countHeart readings during and just after workouts and breathers are set aside, so a run never reads as stress.
- Snooze itIn a meeting? Snooze alerts for an hour straight from the alert.
plain answers, with sources.
How your cortisol score works
What goes in, how your usual is learned, and why it changes.
Can Apple Watch measure cortisol?
No watch can read cortisol. Here is what Apple Watch actually measures, how those signals relate to stress, and how cortisol is really tested.
How to check your HRV on Apple Watch
Where to find heart rate variability on iPhone and Apple Watch, what the number means, and why comparing it with your own normal matters more than any "good" value.
straight answers.
Is Cortisol IQ free?
Free to download. The score needs a weekly or yearly subscription that renews automatically until you cancel in Settings → your name → Subscriptions. You'll see the price before you pay.
Does it measure cortisol?
No. Measuring cortisol takes a lab test of your blood, urine or saliva. Your cortisol score estimates how far your heart rate, sleep, HRV and breathing sit from your own usual. How it works →
Which Apple Watch do I need?
Any Apple Watch on watchOS 11 or later. You don't need the newest model.
Will my watch buzz all day?
No. Alerts only come after about an hour above your alert level, at most two a day and never overnight. You can snooze them or switch them off.
Why doesn't my score match my friend's?
Each score is compared with that person's own usual. An HRV that's low for one person is an ordinary day for someone else.
What happens to my Health data?
Cortisol IQ reads your data, and adds only workouts you choose to save. Scoring happens on your phone and watch. We never sell Health data or use it for ads. Privacy →