Stress & HRV tracking for Apple Watch
4.4 · 107 ratings · US App Store · 2026-09-27

Understand your stress
with Cortisol+.

Bring your Apple Watch HRV, sleep and activity into one daily view. Explore recovery habits and try guided breathing. The wellness score is an estimate; it does not measure cortisol in blood, saliva or urine.

Download on the App Store Get it on Google Play How the score works →
  • Free to download
  • Apple Watch
  • Core scoring on-device
Now · example
Tue · 2:34 PM
CORTISOL
26
LOW
avg 26
Tap for details
HRV
58 ms
Resting HR
58 bpm
Cortisol
Average
32
High
48
Low
23

Example values from the app's Now screen. The score is a wellness estimate, not a hormone measurement.

Inside the app

Explore the app

The same screens you'll find on the App Store: the Now dial, Insights, Sleep, Fitness, Bio Age and Zen. Screens show example values; their score labels do not establish hormone levels or clinical outcomes.

Cortisol+ Now screen with an arc dial showing an example score of 26 labeled Low, HRV 58 ms, resting heart rate 58 bpm, and a Cortisol card with average 32, high 48 and low 23
Now
Live stress levels
The Now dial, HRV and resting heart rate at a glance, plus your day's average, high and low.
Cortisol+ Insights tab on iPhone with a day picker, a suggestion card, Cortisol average 26, Sleep 7.8 hours at 96% quality with 1.3 hours deep, and Recovery with HRV 58 ms, resting heart rate 58 bpm and VO2 max 44.0, next to the Apple Health icon
Insights
Insights from your wearable
A daily suggestion, then cortisol, sleep and recovery cards built from Apple Health data.
Cortisol+ Sleep tab showing an example night scored 93 Excellent, 7 hours 47 minutes asleep, 96% efficiency, fell asleep 11:12 PM, woke 7:00 AM, and awake, REM, light and deep sleep stages
Sleep
Optimize your sleep quality
A nightly quality score, time asleep, efficiency and a stage-by-stage timeline.
Cortisol+ Fitness view with a weekly Readiness chart showing 71 Good, cardio load 14, 9,140 steps, VO2 max 44.0, and workout tiles for bike, strength, run, swim and yoga
Fitness
Track all your activities
Weekly readiness, cardio load, steps and VO₂ max, with runs, rides, swims, strength and yoga.
Cortisol+ Bio Age screen showing an example Bio Age of 26, 4 years younger, a Pace of Aging of 0.88x on a slower-to-faster scale, and sleep, HRV and resting heart rate tiles
Bio Age
Discover your Bio Age
An estimate of your pace of aging from recovery data, and what's affecting it.
Cortisol+ Zen chat where the user asks "What's driving my score today?" and Zen explains the example score of 26 using sleep, HRV and resting heart rate
Ask Zen
Insights from an AI assistant
Ask Zen what's driving your score and get a plain-English answer from your own numbers.
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4.4
107 ratings · US App Store

Loved by early users

4.4 out of 5 stars across 107 ratings on the US App Store, checked September 27, 2026. People with Apple Watches who actually want to understand their stress.

Download on the App Store
Real reviews · App Store

What users say

4.4 from 107 ratings

This app has everything!!

"This app has everything I need for my fitness journey. I needed something to track my stress and cortisol levels. This tracks my Blood O2 levels, resting heart rate and HRV. Really cool. It also tracks my sleep and my activity. I connected with friends and we are sharing our progress with each other. This is actually cool."
— JosephFerry65 · App Store review · v1.9

This actually helped

"I've been using for the past 2 weeks and noticed my stress and anger is down tremendously"
— Roof Rite Construction · App Store review · v1.3
What's inside

Your wearable readings,
in one place. Explore stress and recovery patterns.

Now

Live stress score

HRV, resting heart rate and sleep turned into one score through the day, with the inputs a tap away.

See how it works → Sleep

Sleep quality

A nightly score with time asleep, efficiency, stages, and an overnight chart of heart rate, HRV, breathing and oxygen.

See your sleep view → Bio Age

Bio Age & Pace of Aging

An estimate of how fast your body is aging from your recovery data, and what's moving it. An estimate, not a medical test.

Get the app → Fitness

Readiness & activities

Weekly readiness, cardio load, steps and VO₂ max, plus runs, rides, swims, strength and yoga, and a monthly recap.

Get the app → Zen

Ask Zen & breathwork

Ask what's driving your score and get an answer from your own numbers, then take a short guided breathing session.

Try a session → Apple Watch

On your wrist

Pebble, Ripple and Bloom change color and mood with your level, or switch to Score mode. Seven complications and one-tap breathing.

Apple Watch guide →

Looking for a cortisol tracker app?

Cortisol+ helps you understand wearable stress signals. Apple Watch does not measure the cortisol hormone, and the app does not replace a laboratory test. Start with our Apple Watch cortisol guide and score methodology.

Free download, subscription analysis

Download Cortisol+ for iOS 17 or later. Core analysis requires an active subscription or an eligible trial. Prices, trial eligibility and renewal terms are shown in the app before purchase. Our website's reflection tools and printable journal are free.

The cortisol library

Symptom by symptom, food by food. The complete guide to understanding and lowering cortisol — written by the team building the tracker.

Start with the cortisol guide →