Guide
Smart rings, explained in one place.
A smart ring can track your sleep, pay at the till, take a voice note or answer a question, depending on which one you buy. We are building one, so we read a lot about the others. Every guide below gives its short answer first and lists its sources.
The short version. Most smart rings are health rings that read sleep and heart rate for about a week a charge. A newer kind lets you talk to an AI from your finger, either through your phone or, as Lychnos Ring is being designed, over its own connection. What decides whether one suits you is the job you want it to do, the fit, the battery, whether it needs your phone, and what its plan pays for.
Choosing one
- How to choose a smart ring: what it is for, the fit, battery, plan, materials, water and your rights in the EU.
- Smart ring or smartwatch? Battery, sleep, GPS and comfort, with the makers’ own ratings.
- Is an AI ring worth it? What it does well, what it cannot do, and who should buy something else.
- Smart ring size guide: measuring at home, and why smart rings fit differently from jewellery. Or use the ring size calculator.
- What smart rings are made of: titanium, ceramic and resin, and why radio signals care.
- IP68 or 5 ATM? What water ratings test, and what none of them promises.
- Smart ring battery life: the makers’ figures, what drains a ring, and our target.
- Pre-ordering tech: deposits, pledges and your rights in the EU and the US.
AI rings you talk to
- What is an AI ring? Health rings, voice rings and assistant rings, from button to answer.
- AI rings, compared: talking to an AI, screen, speaker, phone needed, price and plan.
- A ring that talks back: answers at your ear, in your earbuds, as a buzz and a line of text.
- A ring with a screen: what a see-through 72 × 40 screen can show, and why it stays dark until you look.
- Haptic feedback: the motors behind a buzz, and how patterns can say yes, no or not sure.
- Hold to talk or wake word? When the microphone is on, and why that matters.
- Why an AI ring needs a plan: what a subscription pays for, and what to ask of any plan.
- AI ring or AI glasses? A screen in front of your eyes, or an assistant on your finger.
- AI wearables in Europe: which reach Europe, which ship only to the US.
Health and sleep on a ring
- Are smart rings accurate? What studies against sleep labs found.
- What is heart rate variability? And why your number is your own.
- What is a normal resting heart rate? What moves it, and when to see a doctor.
- Can a smart ring track your health in real time? What it measures when, and where wellness ends and medicine begins.
- Can a smart ring replace a blood test? What light through the skin can tell you, and the FDA on glucose.
- How much sleep do adults need? And orthosomnia, when chasing a sleep score keeps you awake.
- Why our first ring has no health sensors, yet: conversation and battery first.
Paying and connecting
- Paying with a ring: a chip, an antenna and a token, and the EU’s contactless limits.
- How tap to pay works: NFC and payment tokens, in the moment you tap.
- The future of payments in Europe: instant transfers, Wero and the digital euro.
- What is an eSIM? In phones, watches and rings, and why it does not pay.
- What is LTE-M? A mobile network made for small devices on small batteries.
- What is Bluetooth LE Audio? Sound for earbuds, hearing aids and small wearables.
Ring by ring
- Lychnos Ring and Oura Ring 5: an AI ring and a health ring.
- Lychnos Ring and Samsung Galaxy Ring: talking to it, or tracking with it.
- Lychnos Ring and Pebble Index 01: an assistant, or simple voice notes.
- Lychnos Ring and Sandbar Stream: answers on the ring, or through your earbuds.
- Lychnos Ring and Vocci Ring: on sale in the US, in development for Europe.
- Lychnos Ring and Spark Ring: catching ideas, or getting things done.
- Lychnos Ring and Natura Interface: AI agents through your phone, or on the ring.
- And beyond rings: Bee, Plaud NotePin and Rabbit R1.
From our workshop
- Speech on a ring: running speech recognition through a ring’s small microphone.
- What our ring and robot learn, and the part that does not learn.
- Call your drone with a ring: how Lychnos Ring and Alkyon are designed to work together.
How we write these
Each guide says when its sources were read and what they cannot show; product details come from the makers’ own pages and change over time. Lychnos Ring is in development, and our figures for it are design targets until they are measured. More in how we write.
Questions
What can a smart ring do?
It depends on the kind. Health rings estimate sleep, heart rate and temperature trends; voice rings capture what you say for an app or an AI; assistant rings answer you on the ring. Some can also pay at a contactless terminal. Our guide to what an AI ring is sorts them out.
Is a smart ring better than a smartwatch?
Neither is better in general. A ring is easier to sleep in and lasts longer on a charge, going by the makers’ ratings; a watch has a screen, apps and its own GPS. Our comparison sets them side by side.