What is a normal eGFR level by age?

An eGFR of 90 or above is generally normal in young adults. eGFR falls naturally with age — many healthy people over 60 sit in the 60–89 range (KDIGO stage G2) without having kidney disease. A reduced eGFR is only labelled chronic kidney disease when another marker of damage, such as protein in the urine, is also present.

How do you convert serum creatinine to eGFR?

You apply the CKD-EPI 2021 equation: eGFR = 142 × min(Scr/κ,1)^α × max(Scr/κ,1)^−1.200 × 0.9938^Age, with an extra ×1.012 for females. κ and α are 0.7 and −0.241 for women, 0.9 and −0.302 for men, and Scr is serum creatinine in mg/dL. This calculator does the arithmetic for you and also accepts µmol/L.

What eGFR level indicates chronic kidney disease?

An eGFR below 60 mL/min/1.73m² sustained for three or more months indicates CKD on its own (stages G3a, G3b, G4, G5). Between 60 and 89 (G2) it is CKD only if there is another sign of kidney damage. A single low reading should be repeated and confirmed by a doctor before any conclusion.

What is the difference between the old CKD-EPI 2009 and the 2021 race-free equation?

The 2009 equation included a coefficient that raised the estimated eGFR for people recorded as Black, which research found was not biologically justified. The CKD-EPI 2021 equation removes race entirely and re-fits the constants (the lead term is 142). This tool uses the 2021 race-free version, now recommended by the National Kidney Foundation and used by major labs.

Is an eGFR of 60 considered kidney failure?

No. An eGFR of 60 sits at the top of stage G3a (or bottom of G2) — reduced, but far from failure. Kidney failure is stage G5, an eGFR below 15. An eGFR of 60 means follow-up and confirmation with a doctor, not an emergency, but it should not be ignored.

Why does this matter for people in Sri Lanka's dry zone?

Sri Lanka has a well-documented epidemic of Chronic Kidney Disease of uncertain etiology (CKDu) in dry-zone farming districts such as Anuradhapura, Polonnaruwa and parts of the Uva and North Western provinces. Regular creatinine screening is a public-health priority there. Many labs print only creatinine, so this tool helps people read their report before a clinic visit — it does not replace one.

Can I use this for a child or during pregnancy?

No. The CKD-EPI 2021 equation is validated for non-pregnant adults aged 18 and over, so this tool blocks ages under 18. Children need the paediatric “bedside Schwartz” equation, and pregnancy, acute kidney injury and extreme muscle mass all make creatinine-based eGFR unreliable. In those cases, rely on a doctor's assessment.

My lab reports creatinine in µmol/L — does that work?

Yes. Toggle the unit to µmol/L and enter the value directly. The tool divides by 88.4 (the standard IFCC conversion) to get mg/dL before applying the equation, and echoes both units back so you can check the conversion. For example, 115 µmol/L equals about 1.30 mg/dL.

Health · Kidney function

eGFR Calculator — Kidney Function & CKD Stage (CKD-EPI 2021)

Turn a serum creatinine reading into your estimated GFR and KDIGO kidney-disease stage in seconds. Uses the race-free CKD-EPI 2021 equation, accepts mg/dL or µmol/L, and shows exactly where your result falls. Educational estimate — always confirm with a doctor.

By Induwara Ashinsana— Executive Director, Ryzera TechnologiesUpdated Jun 12, 2026

Estimate your eGFRKidney function

CKD-EPI 2021 · race-free

Educational estimate, not a diagnosis. eGFR is not valid in acute kidney injury, pregnancy, the under-18s, or at extremes of muscle mass. Always confirm with a doctor.

Sex

The equation uses sex-specific coefficients.

Age (years)

Adults 18–110. Validated for adults only.

Serum creatinine

mg/dL

The creatinine value printed on your blood test report.

Examples

Your eGFR

65mL/min/1.73m²

1.3 mg/dL = 115 µmol/L

KDIGO stage

G2Mildly decreased

A mild reduction that is common with age and often not disease. As with G1, this is only labelled CKD when there is an additional marker of kidney damage like albuminuria.

KDIGO G-stages

Stage	eGFR (mL/min/1.73m²)	Meaning
G1	≥ 90	Normal or high
G2	60–89	Mildly decreased← you
G3a	45–59	Mildly to moderately decreased
G3b	30–44	Moderately to severely decreased
G4	15–29	Severely decreased
G5	< 15	Kidney failure

Formula: CKD-EPI 2021 creatinine (race-free) (Inker et al., NEJM 2021). Stages: KDIGO 2024. Coefficients cross-checked against the National Kidney Foundation calculator. Full citations below.

How it works

This calculator implements the CKD-EPI 2021 creatinine (race-free), published by Inker and colleagues in the New England Journal of Medicine in 2021. It estimates the glomerular filtration rate — how much blood your kidneys filter per minute — from a single serum creatinine measurement, plus your age and sex. The result is reported in mL/min/1.73m² (millilitres per minute per 1.73 square metres of body surface area), the standard unit on lab reports.

The equation is:

eGFR = 142
     × min(Scr/κ, 1)^α
     × max(Scr/κ, 1)^(-1.200)
     × 0.9938^Age
     × 1.012   (if female)

Here Scr is serum creatinine in mg/dL, and the two sex-specific constants are:

Female: κ = 0.7, α = −0.241, factor = 1.012
Male: κ = 0.9, α = −0.302, factor = 1.000

The min and max terms create a two-part curve: when creatinine is at or below κ the α exponent applies, and when it is above κ the steeper −1.200 exponent takes over. The 0.9938^Age term lowers the estimate as you get older, reflecting the gradual, normal decline in filtration with age. The 2021 equation is race-free by design — it dropped the race coefficient used in the 2009 version, which was not biologically justified.

If you enter creatinine in µmol/L, the tool first divides by 88.4 (the IFCC standard molar-mass conversion) to get mg/dL, then applies the equation. To guard against arithmetic mistakes, every result is also recomputed by an independent two-branch (piecewise) form of the same equation; the page only displays a number when both agree. Finally, the rounded eGFR is mapped to a KDIGO 2024 G-stage (G1 ≥ 90, G2 60–89, G3a 45–59, G3b 30–44, G4 15–29, G5 < 15). Stages G1 and G2 are only chronic kidney disease when another marker of kidney damage — such as albuminuria — is present, which is why a healthy eGFR of 75 is not, by itself, a CKD diagnosis.

Worked examples

Male, age 55, creatinine 1.3 mg/dL

eGFR ≈ 65 → Stage G2

κ = 0.9, α = −0.302. Scr/κ = 1.3 / 0.9 = 1.4444
min(1.4444, 1)^−0.302 = 1^−0.302 = 1
max(1.4444, 1)^−1.200 = 1.4444^−1.200 = 0.6432
0.9938^55 = 0.7102
eGFR = 142 × 1 × 0.6432 × 0.7102 = 64.9 → 65 (G2, mildly decreased)

Female, age 60, creatinine 0.8 mg/dL (≈ 71 µmol/L)

eGFR ≈ 84 → Stage G2

κ = 0.7, α = −0.241. Scr/κ = 0.8 / 0.7 = 1.1429
min(1.1429, 1)^−0.241 = 1
max(1.1429, 1)^−1.200 = 1.1429^−1.200 = 0.8519
0.9938^60 = 0.6886, female factor = 1.012
eGFR = 142 × 0.8519 × 0.6886 × 1.012 = 84.3 → 84 (G2, mildly decreased)

Male, age 70, creatinine 2.5 mg/dL (CKDu-style screening case)

eGFR ≈ 27 → Stage G4

κ = 0.9, α = −0.302. Scr/κ = 2.5 / 0.9 = 2.7778
max(2.7778, 1)^−1.200 = 2.7778^−1.200 = 0.2935
0.9938^70 = 0.6470
eGFR = 142 × 0.2935 × 0.6470 = 27.0 → 27 (G4, severely decreased)
Action: an eGFR of 27 warrants prompt nephrology referral — see a doctor.

Frequently asked questions

Sources & references

The equation coefficients and KDIGO stage cut-offs on this page were last cross-checked against these sources on 2026-06-12. This is an educational estimate, not a medical diagnosis — always confirm results with a qualified doctor.

Related tools

LiveHealth

A1C Calculator

Convert HbA1c to estimated average blood glucose in mg/dL and mmol/L (and back) using the ADA's ADAG formula, with an A1c⇄eAG reference chart and ADA normal/prediabetes/diabetes range check. Runs entirely in your browser.

Open tool

LiveHealth

Heart Rate Zones

Find your maximum heart rate and the five training zones in exact bpm — recovery, fat-burn, aerobic, threshold and VO₂ max. Add your resting HR for personalised Karvonen targets. Runs entirely in your browser.

Open tool

LiveHealth

Calories Burned Calculator

Estimate how many calories you burn walking, running, cycling, swimming, the gym, cricket, or 90+ activities from your body weight and duration, using published MET values. Includes a steps-to-calories mode. Runs in your browser, sources cited.

Open tool

Rate this tool

Be the first to rate

Comments & feedback

Spotted a bug or want an improvement? Tell us — our team reviews every comment, and good ideas get built. Comments are public and anonymous.

Found a bug, edge case, or want to suggest an improvement?

Email me at [email protected] — most fixes ship within 24 hours.