Your blood results. A clearer view of age.
Your calendar age counts birthdays. Blood clocks offer another perspective, using the markers in your results to estimate biological age. EvidaLife brings those readings together so you can see the models, the markers and the changes over time.
The Age Quotient puts age in perspective.
Age Quotient = blood biological age ÷ calendar age
Below 1.00, your estimated blood age is younger than your calendar age. Above it, the estimate is older. The ratio lets you read the two ages together, rather than looking at a gap in years alone.
The quotient uses fully measured Bortz-21 when available, with PhenoAge as the fallback. It does not average the clocks. LinAge2 adds context; it does not contribute to the quotient or the League ranking.
Three blood clocks. Three ways to read your results.
Each clock is a published model with its own inputs and weighting. They can disagree on the same draw. The app keeps them visible separately so you can see that difference.
- Bortz-21
Built on UK Biobank data, this model turns routine blood chemistry and a full blood count into an age estimate. When its required inputs are measured, it is the first choice for the Age Quotient. A Core draw can supply its blood markers.
Bortz et al. · Communications Biology, 2023
- PhenoAge
This model combines routine blood markers with your calendar age. It provides a second view of the same results and supplies the Age Quotient when a fully measured Bortz-21 result is unavailable. Its blood markers are also covered by Core.
Levine et al. · Aging, 2018
- LinAge2
The wider view: blood chemistry, blood pressure, resting pulse, weight and a few health questions. It needs the Pro panel inputs and applies within the model’s age range. In EvidaLife it explains biological age; it does not earn points or determine your League rank.
Fong et al. · npj Aging, 2025
See how the clocks read a series of panels.
These are two synthetic sample members. Every value is invented and processed by the same health engine used for members. They illustrate how the charts work, not a typical or promised outcome.
A missing clock is not a zero. Inputs and the model’s age range determine whether a result can be shown. These sample charts do not establish that a particular habit caused a change in biological age.
What these numbers can tell you.
Is the Age Quotient a diagnosis?
No. It is a comparison between a model’s estimate of blood biological age and calendar age. EvidaLife informs and educates. Diagnosis and treatment belong with your doctor.
Why do the clocks disagree?
They use different inputs and give those inputs different weights. Reading them separately keeps those differences visible. The Age Quotient follows its own fixed rule: fully measured Bortz-21 first, then PhenoAge.
Does every upload put me in the League?
No. Uploaded results can inform your personal view. The public League uses eligible partner-lab results and requires your explicit opt-in. Your Age Quotient determines the main ranking; LinAge2 does not.
What if a clock cannot be calculated?
A model needs its required inputs, and some models apply only within a defined age range. An unavailable reading stays unavailable. For the Age Quotient, PhenoAge can serve as the fallback; if neither clock is available, there is no quotient.
Start with the results you have.
You can upload existing lab results to build your personal view. Available markers determine which clocks can be calculated. For a fresh draw, explore the partner-lab panels and what each includes.