Is my resting heart rate from my wearable accurate?

Consumer wearable resting heart rate measurement (optical PPG sensor) is among the most accurate wearable health metrics, agreeing with reference ECG within 2–5 bpm for overnight resting heart rate in multiple validation studies, making wearable-measured resting heart rate one of the most reliable data points your device generates (Shcherbina et al., npj Digital Medicine, 2017).

The specific accuracy conditions: the wearable must be worn with appropriate snugness (one finger's breadth of slack on a wrist device), must not be moved during measurement, and is most accurate during sleep when artifact from movement is eliminated. Daytime spot-check heart rate is less accurate than overnight resting rate, particularly during activities involving wrist movement. For the purpose of tracking resting heart rate trends, consumer wearables are accurate enough to be clinically useful, the same cannot be said for their sleep staging or HRV absolute values.

Honesty Scale: Solid (1) for consumer wearable overnight resting heart rate accuracy.

What to do: Your wearable's overnight resting heart rate is the most reliable daily health metric your device generates. Use it accordingly, track it monthly, not nightly, for the trend signal that matters.

For the full picture, read The Resting Heart Rate Deep Dive