Features/Longevity

How old your body is behaving.

Biological age is the long view of everything else the ring measures — sleep, recovery, heart, movement — expressed as a number you can move. Not a prophecy. A direction, checked every month.

LongevityRing 78%
Biological age 34.2you are 37
2.8 younger
Pillars of ageing
CardiovascularStrong
RecoverySteady
MetabolicWatch
Detected

Your cardiovascular pillar improved through the spring, alongside more zone 2 minutes.

Twelve months

One line you cannot change. One you can.

Biological age · rolling estimate

34.2years

Chronological

37.0

Twelve months ago

37.4

2.8 years younger
12 months ago963Now
Biological Chronological The gap you are building

Chronological age rises at exactly one year per year. The other line is the one worth watching — and a month where it flattens instead of falling is still a month you spent well.

Six pillars

What the number is made of, and what moves each part.

Cardiovascular82

Resting heart rate, HRV and rhythm over months rather than mornings.

Moves with: zone 2 minutes, alcohol, sleep regularity
Recovery64

How reliably you return to your own baseline after load.

Moves with: sleep debt, training balance, stress
Metabolic41

Overnight temperature and heart-rate behaviour, plus what your notes say about late meals.

Moves with: meal timing, late sugar, movement after eating
Cognitive71

REM and deep sleep consistency, the parts of the night most tied to thinking.

Moves with: bedtime consistency, caffeine cut-off
Hormonal68

Temperature rhythm across weeks — and across cycles, if you track them.

Moves with: sleep timing, cycle phase, illness
Environmental57

Travel, time zones, altitude, noise and the nights they cost you.

Moves with: flights, late light, unfamiliar beds

Each pillar borrows its colour from the Circle it draws on, so a pillar and its source data look related wherever you meet them.

What it is built from

Nothing new is measured. It is the same data, read over months.

Longevity does not ask for another test or another wearable. It is the long-window view of the signals the ring already takes every night, which is also why it needs a few months before it says much.

  • WindowRolling 90 days, updated monthly rather than daily — a bad week should not age you.
  • InputsResting heart rate, HRV, sleep architecture, temperature rhythm, activity load, breathing rate.
  • ContextYour tagged notes: alcohol, travel, illness, late meals.
  • First estimateAfter roughly three months of wear. Before that the app says so.
  • ModelA physiological model of Circular's own, weighted across the six pillars. It does not reproduce a laboratory or epigenetic clock.
Detected patterns

The app tells you which change did it.

"Cardiovascular improved through the spring"

Your resting heart rate fell 4 bpm across ten weeks, alongside a rise in zone 2 minutes. The pillar moved with it.

"Metabolic is your slowest pillar"

Overnight temperature runs high on days with late meals — 14 of your last 20 tagged late dinners.

"Cognitive follows your bedtime, not your total"

REM consistency tracks how regular your bedtime is more closely than how long you sleep.

"Travel costs you about three nights"

Across six trips, your environmental pillar dipped for three nights and recovered by the fourth.

Milestones

Progress you can actually reach.

90 nightsEnough wear for a first biological age estimate.Reached
Zone 2150 minutes a week for eight consecutive weeks.6 of 8
BedtimeWithin a 45-minute window for a fortnight.Reached
Alcohol-freeTen consecutive nights, and the HRV that follows them.Not started
Sleep debtUnder an hour for a full month.In progress

No streaks to lose and no badge for a perfect year. Milestones stay available until you reach them.

Honesty

What a biological age is not.

It is a model, built from what a ring can see. It is not a blood test, not an epigenetic clock, and not a life expectancy. Its value is that it moves when your habits move — and that it does so slowly enough to be believable.

  • Not a diagnosisCircular is not intended to diagnose, treat, cure or prevent any disease.
  • Not a blood markerNo epigenetic or laboratory testing is involved.
  • Not a forecastIt describes present physiology, not how long you will live.
  • Comparable only to youTwo people with the same number are not in the same condition.
Questions

Before you read the number.

More in the help centre.

Around three months. Longevity works on a 90-day window, and the app shows how much of it you have filled rather than producing an early guess.

Slowly, by design. A good week does not move it; a changed habit held for two months does. Anything that swung daily would not be measuring ageing.

No. Those use a blood or saliva sample and measure something different. This is a physiological model built from continuous wearable data.

The app names the pillar responsible and what moved with it. Illness, a hard training block or a month of travel all show up here — and all of them recover.

Yes. Longevity is a Circle like any other and can be removed from your home screen entirely.

No. Biological age, the six pillars, detected patterns and milestones are included with the ring, permanently.

Volgende

The daily version of the same idea

See recovery
Man on stone steps wearing the Circular Ring 2 in gold titanium
Leer jezelf kennen. De cirkel is rond.

Start with the next ninety nights.

Wear it through them and the long view starts to belong to you.

Buy now Read the science
Man on stone steps wearing the Circular Ring 2 in gold titanium
Leer jezelf kennen. De cirkel is rond.

Start with the next ninety nights.

Wear it through them and the long view starts to belong to you.