Heart rate
How many times your heart beats each minute.
How: the optical sensor shines light into your skin and watches how much bounces back as blood pulses through.
Optical heart sensorAll day
The specification
Ondori, in detail.
A soft woven band around a small sensor module. Designed for day-and-night wear, it tracks signals from your heart, skin and movement and explains them on your phone. There's no screen, on purpose.
In development · figures are targets for the first production run
0screens. The data lives on your phone
3sensors: optical heart, skin temperature, motion
11readings and scores, explained below
5+ daysbattery life target per charge
24/7made to wear day and night, sleep included
What's inside
The hardware
The target mid-tier configuration for Ondori's first version. Items marked to be confirmed are waiting on the manufacturer's measured figures.
Sensing
- Optical heart sensor
- PPG (photoplethysmography): LEDs and a light detector read blood flow at the wrist.Heart rate, heart-rate variability and blood oxygen (SpO₂)
- Skin temperature
- A temperature sensor against the skin.Read at regular intervals, not continuously, on this version
- Motion sensor
- Accelerometer (IMU).Steps, activity, strain and sleep movement
- Haptics
- Vibration motor for silent alarms and reminders.
Power
- Battery
- 160 mAh rechargeable lithium-polymer cell.
- Battery life
- Target: five or more days per charge with 24/7 wear. measured figure to be confirmed
- Charging
- Magnetic pogo-pin dock.
Build
- Display
- None. One green status light and one button.
- Module
- Brushed-steel sensor module on the side of the band.
- Strap
- Soft woven textile with an adjustable double-loop slider. No buckle to catch.
- Water
- Water-resistant for everyday wear. rating to be confirmed
- Size and weight
- to be confirmed
Connection
- To your phone
- Bluetooth Low Energy, syncing to the Ondori companion app.
- Where you see it
- Everything appears in the app: daily scores, sleep, trends and session reports.
- GPS
- None built in. Distance is estimated from your steps.
What it measures
Every number, in plain English
The band reads a handful of signals directly. Ondori's app turns them into the scores you'll actually use.
Read by the bandWorked out by the app from those readings
Heart rate variability (HRV)
Your heartbeats aren't evenly spaced. HRV is the small variation in time between them. Trends are most useful against your personal baseline, alongside how you feel and train.
How: timed beat to beat from the optical signal, overnight while you're still.
Optical heart sensorOvernight
Resting heart rate
A steady heart rate taken while you sleep. Changes from your usual range can have many factors, including training, stress, temperature, illness and medication.
How: taken from your heart rate during sleep.
Optical heart sensorOvernight
Blood oxygen (SpO₂)
A wellness estimate of the share of haemoglobin carrying oxygen. Values can be lower at altitude, and movement, circulation, skin temperature and other factors can affect accuracy.
How: the optical sensor compares how your blood absorbs red and infrared light.
Optical heart sensorOvernight
Skin temperature
Your wrist skin temperature, shown as a change from your own baseline rather than a single reading, because shifts tell you more than the number.
How: a skin-contact sensor, read at regular intervals.
Temperature sensorOvernight trend
Sleep stages
Your night split into awake, light, deep and REM sleep, plus how long you slept and how often you woke.
How: worked out from how you move and how your heart rate changes through the night.
Motion sensorOptical heart sensor
Steps and distance
How much you moved, and roughly how far.
How: the motion sensor counts steps; distance is estimated from your steps and stride. There's no GPS.
Motion sensorAll day
Active energy
The calories you burned by moving, on top of what your body uses at rest.
How: estimated from your heart rate and movement, with your age, height and weight.
Heart rateMovement
Strain
How hard a workout, or a whole day, worked your heart. 0 is a lazy Sunday; the high teens and beyond take a race or a mountain.
How: built up from the time you spend at raised heart rates, relative to your own maximum and resting rates.
Heart rateMovement
Recovery
A training-readiness estimate from your recent signals. A high or low score adds context; it is not a medical instruction.
How: your overnight HRV and resting heart rate, compared with your own baseline.
HRVResting heart rate
Heart-rate recovery
How far your heart rate falls in the minute after you stop a hard effort. Faster recovery often accompanies better fitness, but the effort and conditions matter.
How: measured from heart rate at the end of a session.
Heart rateAfter workouts
ECG Ondori ECG only
An electrocardiogram: a recording of the electrical signal of your heartbeat, intended here as a wellness reference rather than a diagnosis.
How: a single-lead reading, taken on demand by touching the module. Planned for the second version.
ECG electrodesOn demand
From every side
One module, one strap
The sensor module sits on the side of the band, so the face of your wrist stays plain. The logo goes on the clasp side.
Two versions
Ondori, and Ondori ECG
Ondori
The launch version- Heart rate, HRV and resting heart rate
- Blood oxygen (SpO₂)
- Skin temperature, at regular intervals
- Sleep stages: light, deep and REM
- Steps, distance, activity and strain
- Vibration alarms and reminders
Ondori ECG
Planned for later- Everything in Ondori
- Plus single-lead ECG for heart-rhythm readings
Straight answers
What it doesn't do
No screen
Not even the time. That's the point.
No blood pressure
Neither version measures it.
No GPS
Distance comes from your steps. Carry your phone if you want a mapped route.
Not a medical device
Readings are for wellness and reference, not for diagnosing or treating anything.
Want one when it's ready?
Join the waitlist. We'll write when there's news, and nothing else.
Ondori is in development. Specifications are targets for the first production run and may change before launch. Ondori is a wellness product, not a medical device: its readings are for reference and aren't intended to diagnose, treat or prevent any condition. Talk to a doctor about any health concern.