What is a normal HRV?
There is no single healthy HRV number. The useful comparison is your own recent nights.
Last reviewed 2026-09-24 · Sources · Editorial policy
01Why charts of normal HRV mislead
Published ranges for heart rate variability are wide, and they mix different formulas. SDNN from a watch is not the same number as RMSSD from a chest strap or a ring. Comparing your Apple Health sample to a blog’s good HRV table mostly creates anxiety.
02What Early Signal compares
The app builds a personal median and MAD from your valid nights. Today’s HRV is a supporting signal: it can agree with temperature, breathing, and resting heart rate, but it does not set Off from usual by itself.
03What a drop can mean
Training, short sleep, alcohol, travel, stress, and feeling run down can all lower HRV. The app does not assign a cause. If you feel unwell, that matters more than the millisecond value.
Guide FAQ
01Should I chase a higher HRV?
02Why does my friend’s HRV look so different?
Sources
Public documentation cited as context—not as clinical validation of Early Signal.
Related guides
HRV drops and a rest-day heads-up—what wearables can show
Heart rate variability often falls when stress load rises. Here is how Early Signal uses HRV as support—not a solo trigger.
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Why a personal baseline beats population averages
Wellness scores that compare you to everyone hide the early personal shifts that matter.
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What else moves HRV and wrist temperature?
Alcohol, travel, training, and a hot room can look like strain. Baselines and context exist for that reason.
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How it compares
Factual comparisons. No prices or ratings.
Band
Early Signal and WHOOP
WHOOP Recovery is a daily readiness score for strain. Early Signal is a rare wellness status from Apple Watch nights.
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Ring
Early Signal and Oura Symptom Radar
Oura looks for strain from a ring. Early Signal looks for a personal pattern from the Watch you already wear.
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