Measure your stress.
Track your recovery.
A 60-second HRV check on your Apple Watch, scored against your own normal, not a generic chart. See where you stand, and what's moving it.
Three steps to your real number
No chest strap, no guesswork. Your Watch does the measuring; your phone does the thinking.
Measure with your Watch
A 60-second guided breathing measurement runs on Apple Watch and captures your beat-to-beat heart rhythm, the basis for real HRV.
Track on your phone
Your history, trends, and plain-language explanations all live in the iPhone app, clear, calm, and yours.
Learn your personal normal
The score isn't absolute, it's calculated from your own history, so a number finally means something for you.
Serious HRV, made calm
The metrics researchers actually use, wrapped in an interface that never makes you anxious about your anxiety.
Real HRV, done right
Beat-to-beat intervals from your Watch, artifact-cleaned and turned into lnRMSSD, the metric clinicians trust, not a vague "stress %."
Your personal normal
A baseline engine learns your usual range, so each score is a deviation from your own normal, with a confidence rating, never false precision.
Trends & what moves them
Long-term trends plus correlations with sleep, resting heart rate, respiratory rate, and the factors you tag yourself.
AI analysis, on device
An on-device AI phrases your result in plain language. The numbers are computed by our code; the model never leaves your phone.
Mood & context check-ins
Add how you actually feel and what's going on. Over time, StressCheck shows which of your factors line up with better recovery.
Watch app & widgets
Measure right from your wrist, glance at your latest score with iPhone & Watch widgets, and keep a full history in sync.
The measurement happens on Apple Watch
Your Watch reads the tiny timing changes between heartbeats that a finger-on-camera reading can't. Start a 60-second guided session on your wrist; your iPhone turns it into a score you can understand.
Your heart data never leaves your devices
StressCheck reads from Apple Health and runs entirely on your device. There's no account and no server of ours, even the AI analysis runs on-device, so nothing about your heart is ever uploaded.
Free to measure. Plus to go deep.
Take measurements, see your score and personal normal for free. StressCheck Plus unlocks the long game.
StressCheck
- Unlimited 60-second measurements
- Score, recovery state & personal normal
- Mood check-ins & on-device AI analysis
- Long-term trends & advanced metrics
Plus
- Extended history & long-term trends
- Advanced metrics, breakdowns & correlations
- Everything in Free, of course
- Supports a private, on-device indie app
