Happy Health has announced FDA clearance for its Happy Ring to measure systolic and diastolic blood pressure without a cuff or individual calibration. The feature is cleared for adults aged 22-50 and can be used at home or in clinical settings.

The clearance adds another clinical function to a smart ring that has already received FDA clearance for physiological monitoring and at-home sleep testing.

Measuring blood pressure from the finger

The blood-pressure software combines optical PPG signals with electrodermal activity, skin temperature, and movement. It uses signal processing and a biophysics-based model to estimate blood pressure in mmHg.

Many cuffless systems require an initial or periodic reference measurement from a conventional blood-pressure cuff. Happy Ring can generate readings without users first entering their blood pressure or providing demographic information.

Happy Health validated the system in 85 participants across 850 paired measurements against invasive arterial-line readings. Mean error was 0.81 mmHg for systolic pressure and 0.12 mmHg for diastolic, with standard deviations of 6.09 and 3.16 mmHg respectively. The system met ISO blood-pressure accuracy criteria.

The clearance currently covers spot-check measurements and does not extend to continuous readings or hypertension diagnosis.

Building a broader home-care platform

Happy Health is developing the ring as part of a physician-led home-care platform. Its existing FDA-cleared sleep test allows patients to undergo multi-night monitoring for conditions such as obstructive sleep apnoea, with physicians reviewing the results and guiding care.

Adding blood pressure is particularly relevant because sleep apnoea is closely associated with hypertension. The combination gives clinicians access to both measurements through the same device, potentially helping them understand how sleep-related conditions and blood pressure interact.

The Austin-based company raised $75 million in August 2026, led by ARCH Venture Partners and OpenLoop, to expand its home-care platform.

Happy Health now joins a growing field of companies bringing blood-pressure measurement into everyday wearables, an area we recently explored in our overview of the wearable blood-pressure market.