ARO ONE SMART RING
The tracker you forget you're wearing.
Aro One weighs less than a coin, has no screen to distract you, and runs for days on a single charge. Slip it on and it quietly maps how you sleep, how hard you push, and how well you bounce back.
Why a ring instead of a watch
| Aro One Smart Ring | Typical smartwatch | |
|---|---|---|
| Comfortable to sleep in | Yes | Most people take it off |
| Battery between charges | Days | Usually overnight |
| Screen and notifications | None at all | Constant |
| Weight on the body | About 3–4 g | 30–60 g |
| Monthly fee to read your data | $0 | Often required |
| Works with a dress shirt cuff | Invisible | Bulky |
| Price | $49.95 | $200–$400 |
What Aro One tracks
Sleep.
Time asleep, restlessness, and how your nights trend across weeks — the part that actually tells you something.
Heart rate trends.
Continuous readings through the day and overnight, so you can see how your baseline shifts.
Activity & steps.
Movement, active minutes and calorie estimates without strapping anything to your wrist.
Readiness.
A daily score that blends your sleep and recent activity into one honest answer: push today, or take it easy.
Specifications
- Material
- Aluminium-alloy shell, skin-safe inner coating
- Weight
- About 3–4 g depending on size
- Battery
- Multi-day use, ~90 min to full
- Water resistance
- Handwashing, sweat and rain
- Connectivity
- Bluetooth, iOS and Android
- Finishes
- Black, Gold, Silver — standard and Pro
- Sizes
- US 6, 7, 8, 9, 10, 11, 12, 13, 14
In the box
- ARO ONE Smart Ring in your chosen size and finish
- Magnetic charging dock
- USB-C charging cable
- Quick start guide
Getting the size right
Ring sizing matters more than with a watch, so measure before you order. Wrap a strip of paper around the base of your finger, mark where it overlaps, and compare that length to a standard ring size chart. Measure at the end of the day when your fingers are at their largest, and measure the finger you'll actually wear it on — most people choose the index or middle finger. Between two sizes? Go up.
Sized wrong? Message us within 30 days and we'll swap it.
Ordering
- Free shipping on every order
- Typically arrives in 10–16 business days
- 30-day returns and exchanges
- Tracking sent as soon as your ring leaves the warehouse
A note on health data. Aro One Smart Ring is a general wellness and fitness product. It is not a medical device, has not been evaluated by the FDA, and is not intended to diagnose, treat, cure or prevent any disease or condition. Readings are estimates meant to help you spot patterns over time, not clinical measurements — don't use them to make medical decisions. If you have concerns about your heart, your sleep or your health generally, talk to a qualified healthcare professional.
ARO ONE Smart Ring — Sleep, Recovery & Activity Tracker
Before you order
How do I know my ring size?
Wrap a strip of paper around the base of the finger you'll wear it on, mark where it overlaps, and measure that length in millimetres against our chart. Measure at the end of the day, when your fingers are largest.
What if I order the wrong size?
Message us within 30 days and we'll arrange an exchange. Sizing from a chart is hard to get right and we don't hold it against you.
How long does delivery take?
Typically 10 to 16 business days within the US, with free shipping. We ship directly from our manufacturing partner, which is what keeps the price at $49.95. The trade-off is a longer wait, and we'd rather tell you here than bury it at checkout.
Is it a medical device?
No. Aro One is a general wellness and fitness product, not intended to diagnose, treat, cure or prevent any condition. Readings are estimates for spotting trends, not clinical measurements.