Biological age tests explained
Levine, PhenoAge, GrimAge, Horvath, DunedinPACE, OMICmAge: they sound interchangeable, but they aren't. This guide covers what each one measures, why your results can disagree and which Australian providers use which method.
Prices and studies checked 4 Nov 2026
The short version
- "Levine" and "PhenoAge" usually mean the same thing. Morgan Levine built PhenoAge, and it comes in two versions: one from a standard blood test and one from a DNA test.
- There are three main families: blood chemistry, DNA methylation (epigenetic) and glycan tests. Telomere tests are a fourth, older approach.
- Most clocks give you an age. DunedinPACE gives you a speed.
- Different clocks often disagree. They measure different things, so that isn't a sign that a test is broken.
- Blood PhenoAge is the cheapest route. It's worked out from nine blood markers, so routine bloods can supply it if they include all nine.
The families of tests
Blood chemistry (such as Levine PhenoAge)
This uses ordinary pathology results plus your calendar age. The formula uses nine markers: albumin, creatinine, glucose, C-reactive protein (CRP), lymphocyte percentage, mean cell volume, red cell distribution width, alkaline phosphatase and white blood cell count. It was built on a large US population survey, NHANES (Levine et al., 2018).
It's cheap and uses standard labs. But some of its markers can change in the short term, and the score moves with them.
Epigenetic (DNA methylation) clocks
These read chemical tags on your DNA, from blood, saliva or a cheek swab. The tags shift in patterns as you age. Horvath, DNAm PhenoAge, GrimAge, DunedinPACE, OMICmAge and most branded "epigenetic age" tests sit here. They cost more, results often take weeks, and the score depends on the lab and the algorithm.
Glycan age
GlycanAge measures 29 sugar structures attached to IgG antibodies, and frames the result around chronic inflammation (GlycanAge). It isn't an epigenetic clock, so don't expect it to match one.
Telomere tests
Telomeres are protective caps on the ends of chromosomes that shorten as cells divide. Telomere length was one of the first biological age measures. Some Australian providers still sell it, on its own or beside a blood age.
The main clocks
Researchers group epigenetic clocks into generations by what they were trained to predict: calendar age, then disease and death, then change in health over time (Arpawong et al., preprint).
- 1st generationTrained to predictCalendar ageHorvath, HannumReads like an odometer
- 2nd generationTrained to predictDisease and deathPhenoAge, GrimAgeReads like an odometer
- 3rd generationTrained to captureChange in health over timeDunedinPACEReads like a speedometer
| Clock | Generation | The question it answers | You get |
|---|---|---|---|
| Horvath, Hannum | 1st | "How old do your cells look?" Horvath uses 353 DNA sites (Biogerontology, 2026) | An age in years |
| PhenoAge (Levine) | 2nd | "How old does your health look?" The DNA version uses 513 sites (Levine et al.) | An age in years |
| GrimAge | 2nd | "What's the long-term risk?" Described as consistently the strongest epigenetic predictor of mortality (preprint) | An age in years |
| DunedinPACE | 3rd | "How fast are you ageing right now?" Built from 19 markers tracked at ages 26, 32, 38 and 45 (Belsky et al., 2022) | A rate (1.0 = average) |
| Brand clocks (OMICmAge, MuhdoAge) | Varies | Set by each brand | Usually an age, sometimes system or organ ages |
Odometer or speedometer
Age clocks such as Horvath, PhenoAge and GrimAge work like an odometer: they estimate how much ageing has built up. DunedinPACE works like a speedometer: it estimates the pace now. A result of 1.0 means one year of biological ageing per calendar year, and 1.2 means about 20% faster (Clinical Epigenetics, 2025). Its developers report high test-retest reliability (Belsky et al.), which is why it's often used for repeat testing.
Organ and system ages
Some tests split your result into separate ages for the heart, liver, kidneys and so on. TruAge reports 11, and TMRW's add-on reports organ-system ages. These are newer than the headline clocks and aren't a diagnosis. Questions about a score are for your GP.
Why results disagree
- They measure different things. In one study of 86 women, PhenoAge and GrimAge results moved together moderately (r = 0.54), while DunedinPACE had little correlation with PhenoAge (0.03) or GrimAge (0.14) (Ferreri et al., 2026).
- Scores shift between tests. One research group reports that re-testing the same person can move results by 0.9 to 2.4 years (Aging Cell, 2026). In its 2022 study, technical noise made repeat runs of the same sample differ by up to 9 years on six well-known clocks. Its retrained "PC" versions agreed within 1.5 years for most repeats (Higgins-Chen et al.).
- Everyday life adds noise. Clocks are highly consistent when the same sample is run again, but much less stable across samples taken hours or days apart, around meals, stress or pollution (Aging Cell, 2026).
There's also no consensus yet on how these measures should be validated before clinical use (Moqri et al., Nature Medicine, 2024). So a one- or two-year change on a single retest may be noise. Comparing the same clock from the same provider, under similar conditions, gives a fairer trend.
Disclosure from the 2026 study of 86 women: four authors work for TruDiagnostic, which sells the TruAge test listed below. Its figures are for the age-acceleration versions of PhenoAge and GrimAge, from a side analysis in a diet study.
Disclosure from the 2022 paper: two authors built metrics licensed to Elysium Health through Yale University, Elysium provided some of the data, and one author was a paid Elysium adviser.
Which Australian providers use which method
Prices are in Australian dollars, from each provider's own site. Grouped by method, not ranked. Compare listings carry their own check dates on the DNA and blood test tables; everything else here was checked 4 Nov 2026.
Blood-based
| Test | Method | Sample | What you get | Price |
|---|---|---|---|---|
| Bloody Good Biological Age Test | PhenoAge, named on its page Bloody Good | Blood at a collection centre, after a 10-hour fast | A biological age score | $58shown as a sale price |
| i-screen Biological Age Test | PhenoAge, nine blood markers i-screen | Blood at a collection centre, after an 8 to 12-hour fast | A PhenoAge score | $59shown as a sale price |
| Updoc | Levine PhenoAge model, nine named markers Updoc | Blood at a collection centre | A biological age, requested online through a partner doctor | Not statedno test price on the page; consults are priced separately |
| Everlab Baseline | Not named Our listing | Blood | Biological age inside a wider blood panel | $299a year, foundational bloods including biological age |
Epigenetic
| Test | Method | Sample | What you get | Price |
|---|---|---|---|---|
| Elemental Health & Nutrition: TruAge Complete | TruDiagnostic's report. The page names DunedinPACE, GrimAge 2.0, PhenoAge, OMICmAge and SymphonyAge. Elemental | Finger-prick, mailed to TruDiagnostic's lab in Kentucky, US | Results in 5 to 6 weeks, including 11 organ-system ages | $825test only; $1,005 with a telehealth consult. Return postage of about $47 is extra. |
| Wellbeing George: TruAge | TruAge Our listing | Not confirmed on its product page | A broader test than its telomere test below | $995$1,195 with a 60-minute consult |
| Muhdo Health | MuhdoAge, Muhdo's own clock Our listing | Saliva, mail-in | A UK company with an Australian storefront | $900one-off |
| TMRW Cellular Insights | Clock not named Our listing | Not stated | Biological age, pace of ageing and organ-system ages | $99/monthadd-on to a $365 yearly membership; two tests a year |
| HealthScreen | GrimAge, named on its page HealthScreen | Blood at its Sydney or Melbourne clinic | A physician interprets the result | $950add-on only, to its $3,500 program, so $4,450 in total. Included in the $5,900 Platinum program. |
Telomere
| Test | Method | Sample | What you get | Price |
|---|---|---|---|---|
| Wellbeing George: Telomere Test | Telomere length Our listing | Saliva or blood, mail-in | A single-marker test | $310from |
| i-screen Biological Age & Telomere Test | Telomere length, reported as a biological age. Its page doesn't mention PhenoAge. i-screen | Venous blood, using a mailed kit | Biological age (telomere), average telomere length and an "Age Pace" | $315 |
| MediTests Biological Age Test | Telomere length and a biological age result. Formula not named. MediTests | Not stated on the page we read | Both results | $339shown as a sale price |
- US names you may see. Function Health and Superpower list US states only. See the US version of this guide.
- Data location. TruAge samples are processed in the US, not Australia.
- Sale prices are today's price on the provider's page, and can change.
- Sample type. PhenoAge, GrimAge and DunedinPACE were built on blood. Muhdo's saliva test uses its own clock.
What to compare
| If you're looking for… | Method to look for | Where it's sold |
|---|---|---|
| The lowest cost | Blood PhenoAge | Your existing bloods, if they have all nine markers, or Bloody Good and i-screen |
| A measure of current pace | DunedinPACE | TruAge, through Elemental Health |
| A clock trained on mortality | GrimAge | HealthScreen; Elemental's TruAge page also names GrimAge 2.0 |
| No blood sample | Saliva or cheek swab | Muhdo Health |
| An inflammation-based signal | Glycans | GlycanAge (we haven't checked its Australian availability) |
These match a stated fact about each test. They aren't recommendations, and whether to test at all is a question for your GP.
FAQ
Is Levine the same as PhenoAge?
Mostly, yes. Morgan Levine led the research behind PhenoAge, so "Levine PhenoAge" and "PhenoAge" usually mean the same model. Check whether a provider means the blood version or the DNA version (DNAm PhenoAge), because they are different tests.
Which test is most accurate?
There is no single accurate biological age, because each clock answers a different question. GrimAge is described as consistently the strongest epigenetic predictor of mortality, in a preprint not yet peer reviewed. DunedinPACE was built for repeat testing, using only DNA sites with high test-retest reliability.
How often do people retest?
There is no agreed interval. Some providers build in a schedule: TMRW includes two tests a year. Because results vary between samples, a trend across several tests says more than any single change.
Can I get Function Health or Superpower in Australia?
Their published coverage lists US states only. The tests above are the ones we found for sale in Australia.
Can I lower my biological age?
Studies link diet, exercise, sleep and stress to these scores. Whether a lower score means a longer or healthier life for any one person is still being studied.
My biological age jumped several years in six months. What does that mean?
We can't interpret a result for you, so that's a question for your GP. In general, blood PhenoAge uses CRP, white cells and glucose, which can change in the short term, and the repeat-test figures above show how much scores can move between samples.
How this guide was made
Drafted with Claude. We read each study and provider page cited here on 4 Nov 2026; "not named" means we looked and the provider's page didn't say. One source, the paper on clock generations and GrimAge, is a preprint that hasn't been peer reviewed. See how we choose and the glossary.
Not medical advice. Biological age tests aren't diagnostic tools. Talk to your GP about any result. No provider can pay to be listed or for a better position.