See your estimated cortisol rhythm
Compare activation and recovery signals with your personal baseline across the day.
Cortisol rhythm · Stress · Recovery
Build a healthier cortisol rhythm.
Cortisol should rise and fall—not stay permanently low. CortiLoop connects sleep, HRV, heart rate, activity and your daily context to help you understand activation, recovery and the habits that shape your rhythm.
Free at launch · iOS & Android · Built for privacy
Healthier cortisol rhythmPersonal baselineUncertainty shownHealth data stays on device
Measure → Explain → Act → Learn
Cortisol is a rhythm, not a score to minimize.
Cortisol normally helps you wake, focus and respond to demand, then should ease as recovery takes over. CortiLoop helps you understand that daily pattern through wearable signals and context—without inventing a hormone reading.
See what may shape it
Sleep, activity and reported context stay separate from inference, with confidence and plausible alternatives.
Support a healthier pattern
Choose a realistic action for the moment—whether you need useful activation, a reset or better recovery.
Built around your real day
See what may be shaping your cortisol rhythm.
CortiLoop looks beyond a single reading to the routines and recovery signals that repeat across your day.
Wearable data, connected
Bring together sleep, HRV, resting heart rate, activity and workouts from Apple Health or Health Connect.
A baseline that is yours
Compare you with you. CortiLoop learns your recent range instead of forcing everyone into the same “ideal” number.
Check-ins that take seconds
Add just enough context—energy, mood or an unusual event—to make an explanation more grounded.
Cortisol rhythm insights
Explore estimated activation, physiological load and recovery patterns while seeing the evidence and confidence behind every insight.
Small recovery actions
Get one to three time-matched options, from paced breathing and stretching to a short walk or rest.
Private by design
Core health processing is designed to happen on your device. CortiLoop does not sell health data or use it for ads.
Scientific honesty first
Your watch does not measure cortisol. Neither do we.
CortiLoop is deliberately precise about what is measured, what is reported and what is inferred.
No fake cortisol numbers
We describe estimated rhythm, physiological load and recovery signals—not a cortisol level or diagnosis.
Confidence stays visible
Missing data, a learning baseline or several plausible explanations lead to more cautious language.
Recovery, not permanent calm
Stress can come from exercise, excitement and meaningful challenge. The focus is how you respond and recover.
Wellness, not medical advice
CortiLoop does not diagnose, treat or prevent disease. Health concerns belong with a qualified professional.
Learn the signals
Understand cortisol without the myths.
Learn what a healthy cortisol rhythm means, what wearables can and cannot reveal, and why HRV, sleep and your personal baseline add useful context.
CORTISOL · 8 MIN READ
What is a healthy cortisol rhythm?
Why cortisol normally rises and falls, what can shape the pattern and what wearables can honestly tell you.
Read the guide → 7 MIN READHRV and stress: what the signal can tell you
Why context, timing and your own trend matter more than chasing a universal score.
Read the guide → 8 MIN READHow wearable stress tracking works
What watches and rings measure—and why stress estimates are not cortisol measurements.
Read the guide → 6 MIN READWhy a personal baseline changes the picture
Learn why your normal range is often more useful than a population average.
Read the guide →Frequently asked questions
Good to know before launch.
What does a “healthier cortisol rhythm” mean?
Cortisol has a normal daily rhythm: it generally rises around waking, supports energy and alertness, and trends lower toward night. A healthier rhythm is not permanently low cortisol; it is appropriate activation followed by effective recovery and a pattern that supports sleep and daily function.
Does CortiLoop measure cortisol?
No. Consumer wearables do not directly measure cortisol. CortiLoop interprets sleep, heart rate variability, resting heart rate, activity and reported context to describe an estimated cortisol-related rhythm, physiological load and recovery pattern. It never presents that interpretation as a hormone measurement.
Which wearable data does CortiLoop use?
CortiLoop is designed to read selected sleep, HRV, resting heart rate, steps and workout data through Apple Health on iOS and Health Connect on Android, after explicit permission.
Is CortiLoop a medical app?
No. CortiLoop is a general wellness app. It does not diagnose, treat or prevent disease and its insights are not medical advice.
Early access
Be first to close the loop.
CortiLoop is in development for iOS and Android. Join the waitlist for launch updates and early-access invitations.