New $399 Ring Monitors Blood Pressure Without Cuff Calibration

When Tom Moss landed in the ER with a blood pressure reading of 250 mmHg (more than double the healthy limit), he knew something had to change. But the tech executive couldn't find a wearable device that could track his blood pressure accurately throughout the day without constant recalibration.

So he built one himself.

Moss, an early Android team member and former COO of drone maker Skydio, spent the last three years developing the Signal Ring with two engineers from pulse sensor company Masimo. The device launches this October for $399, promising something no other smart ring has delivered: continuous blood pressure monitoring that doesn't drift between readings.

Most current devices, including Samsung's Galaxy Watch, require users to regularly calibrate their blood pressure readings against traditional cuff monitors. Moss says these readings become unreliable between calibrations, making them potentially dangerous for people managing serious conditions.

The Signal Ring takes a different approach. Users can request manual readings by sitting down, relaxing, and breathing slowly while the device takes measurements. After each reading, you can tag what might have affected your numbers: exercise, coffee, stress, or medication.

Over time, the system learns your patterns and tracks changes passively throughout your day. The goal isn't counting steps or tracking workouts. It's keeping people with hypertension and cardiac issues out of emergency rooms.

The Ripple Effect spreads beyond individual health tracking. Vital Signals is pursuing FDA regulatory clearance to eventually work with insurance companies, potentially making preventative heart monitoring a standard part of healthcare coverage. In January, the FDA started creating broader exemptions for blood pressure readings from optical heart monitors, timing that could help the Signal Ring become a covered medical device rather than just a wellness gadget.

Moss has made strong commitments about what the ring won't do. No monthly subscription fees. No AI features baked into the product. Your blood pressure data remains easily exportable if you want to analyze it with your own tools.

The ring ships with a charging case holding enough power for four recharges (the ring itself lasts three days per charge). It's available in US sizes 5 through 13, and buyers need to order a sizing kit first to ensure proper fit.

Pre-orders open today, with shipping starting in October at the earliest.

For the 116 million Americans living with high blood pressure, a ring that truly tracks heart health around the clock could transform daily life from constant worry into confident management.