eGFR: what is a good level?

An eGFR below 60 mL/min/1.73 m² can be a sign of kidney disease, but one result alone does not establish chronic kidney disease. CKD involves abnormalities present for at least 3 months; kidney disease can also be present at higher eGFR values when other markers of kidney damage are present.

Longevity-optimised target ≥ 90 mL/min/1.73m²

This is the range used by the organ dial in the Longevity Score calculator. It is deliberately tighter than the range printed on a standard lab report — the reasoning is below.

Calculator scoring rangemL/min/1.73m²
Standard
not shown
Optimised
≥ 90 mL/min/1.73m²
3085140

Nothing you type here is sent anywhere, stored, or logged. It never leaves this page.

No reference interval is shown because results and intervals depend on the measurement and clinical context. The brighter band shows the calculator's scoring range. This is not a diagnosis or treatment target.

What eGFR actually measures

An estimate of how much blood the kidneys filter per minute, normalised to body surface area. It is calculated from a blood marker, not measured directly.

Estimates may use creatinine alone, cystatin C alone, or both. The calculator scores cystatin C-based eGFR; these estimates are not interchangeable, and each has limitations. Ask your clinician which result and equation you have before entering it.

Why it matters

Kidney disease can have few symptoms early on. eGFR and urine albumin provide different information that clinicians use together to assess kidney health.

Lower eGFR is associated with higher risks of kidney and cardiovascular complications, but an estimate alone cannot predict an individual's outcome.

Why it's on the dashboard

The organ dial includes cystatin C-based eGFR as an estimate of filtration. The assessment also includes urine albumin-to-creatinine ratio; neither value on its own replaces a clinical kidney assessment. See the Organ dial for the broader context.

Using your result

Bring your results to the Longevity Score assessment for a broader, educational view. It does not replace care from a qualified clinician.

Why this range is stricter than your lab's

The book-based calculator range is a scoring input, not a threshold for diagnosing kidney disease. Clinical interpretation also considers urine albumin, duration, age, health history and the estimating method.

Estimates are less precise at higher filtration rates. Discuss changes over time and the appropriate follow-up with a clinician.

This distinction applies across the whole panel, not just this marker — see optimal versus standard lab ranges for the general case.

What moves eGFR

Blood pressure and glucose
Management can matter for kidney health; goals depend on your circumstances.
Medication
Some medicines affect kidney function or require adjusted dosing. Review them with a clinician rather than stopping them yourself.
Test conditions
Illness, hydration and factors affecting the blood markers can influence estimates.

Educational information, not a treatment plan. Discuss changes to medication or supplementation with a clinician who knows your history.

How fast it responds

Kidney function can change over short or long periods. A clinician can assess the trend and determine whether an unexpected result needs prompt follow-up. See response times across all markers for how this compares.

What can distort the result

Score eGFR against all 8 dials

Frequently asked questions

What is a good eGFR level?

The longevity-optimised target used in this calculator is ≥ 90 mL/min/1.73m². An eGFR below 60 mL/min/1.73 m² can be a sign of kidney disease, but one result alone does not establish chronic kidney disease. CKD involves abnormalities present for at least 3 months; kidney disease can also be present at higher eGFR values when other markers of kidney damage are present.

Why is this target stricter than the range on my lab report?

The book-based calculator range is a scoring input, not a threshold for diagnosing kidney disease. Clinical interpretation also considers urine albumin, duration, age, health history and the estimating method.

How fast does eGFR respond to change?

Kidney function can change over short or long periods. A clinician can assess the trend and determine whether an unexpected result needs prompt follow-up.

eGFR feeds the organ dial, and read it alongside Blood Pressure · HbA1c.

All biomarkers

Sources and further reading

These sources provide general context; calculator scoring ranges are not clinical treatment targets.

Not medical advice. These are longevity-optimised reference ranges, which are deliberately stricter than standard clinical "normal" values. A value outside them does not mean you have a disease. Speak to a qualified healthcare professional before changing medication, supplements or training. Full disclaimer.
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What is a good eGFR level?

The longevity-optimised target used in this calculator is ≥ 90 mL/min/1.73m². An eGFR below 60 mL/min/1.73 m² can be a sign of kidney disease, but one result alone does not establish chronic kidney disease. CKD involves abnormalities present for at least 3 months; kidney disease can also be present at higher eGFR values when other markers of kidney damage are present.

Why is this target stricter than the range on my lab report?

The book-based calculator range is a scoring input, not a threshold for diagnosing kidney disease. Clinical interpretation also considers urine albumin, duration, age, health history and the estimating method.

How fast does eGFR respond to change?

Kidney function can change over short or long periods. A clinician can assess the trend and determine whether an unexpected result needs prompt follow-up.

What is biological age?

Chronological age counts birthdays. Biological age estimates how old your body appears to be functioning, based on measurable biomarkers. Two people born the same year can differ by a decade or more in vascular stiffness, insulin signalling or cardiorespiratory fitness. Biological age makes that gap explicit — and unlike your birthday, it can move in either direction.

How is the Longevity Score calculated?

Each biomarker you enter is scored against longevity-optimised reference ranges and grouped into one of eight dials. Every dial produces its own biological age, and those are combined using fixed weights into a single composite, then expressed as a Longevity Score from 0 to 100. The weighting reflects how strongly each system predicts healthspan: structural and vascular carry the most, hormonal the least.

Do I need all 53 biomarkers?

No. The short form contains a subset of scoring inputs plus context-only fields, and you can leave any of them blank. It is not a recommendation to obtain tests. Missing values are excluded from the calculation — never treated as zero or as 'normal'. A dial with no scored data is dropped entirely and the remaining weights renormalise.

What can I measure without a blood test?

Some inputs can be measured without bloodwork. Blood pressure needs a home cuff and waist-to-height needs a tape measure. Wearable estimates vary; the floor-based sitting-rising test carries a fall risk and should only be attempted if safe.

Is this an anti-aging calculator? Is it a healthspan calculator?

Both terms describe what this tool does, and which one fits depends on what you are asking. "Anti-aging" is the term most people search, and loosely means anything aimed at slowing or reversing age-related decline — this tool fits that description if you score your dials and act on what you find. "Healthspan calculator" is the more precise term: healthspan is the number of years lived without serious chronic disease or disability, and that cannot be measured directly, so this tool scores eight systems that each function as an early-warning proxy for it. Either way, the method is the same: real biomarkers, published thresholds, no vanity-metric framing.

Why don't you have a quick quiz that skips biomarkers entirely?

Several popular tools ask only about habits — exercise days, sleep hours, smoking, diet quality — and return a single precise-looking age. We looked at the research behind that approach and chose not to build it. Published studies do show real, individually-measured links between specific habits and epigenetic age acceleration, but those effect sizes come from different study populations, different DNA-methylation clocks and different measurement units. Adding them together into one number is not something the underlying research actually supports — it produces a precise-looking result built on an imprecise method. Our dials use direct physiological measurements instead: a real blood pressure reading, a real VO₂ max, a real ApoB value. Several dials score from home-measurable data alone with no quiz-guessing involved — see what you can measure without a blood test, above.

Why are your 'optimal' ranges stricter than my lab's normal range?

Standard reference ranges describe what is common in a general population, which now includes a great deal of metabolic dysfunction. They are tuned to flag disease, not to identify what is optimal for a long healthspan. A fasting insulin of 20 µIU/mL sits inside most labs' normal range and is strongly associated with insulin resistance. This tool uses longevity-optimised thresholds instead, so a flag here means room for optimisation — not a diagnosis.

All questions