HR Tracker · Web BLE

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—bpm

RR now— ms

Contact—

Energy— kJ

Beats0

Live beats (sub-second)

Each spike is one real heartbeat, placed using its RR-interval (ms). Quarter-second grid ticks give sub-second resolution.

HRV (rolling window)

RMSSD—ms

SDNN—ms

pNN50—%

SDSD—ms

Mean RR—ms

Mean HR—bpm

RR range—ms

HRV score—/100

Heart rate

RR variability HRV trace

Wider swings = higher variability (more relaxed/recovered). Flat = stressed/fatigued.

Device features full GATT

Every Bluetooth service & characteristic the device exposes, with read/write/notify capabilities. Tap a readable row to fetch its value.

Raw telemetry ms-precise

Tap Diagnostic report, then paste it to share exactly what your device sends. Each HR packet logs the raw bytes, flags byte, sensor-contact bits, and RR intervals in both ms and the BLE native 1/1024 s unit.