Kidney function (eGFR)

Your blood test shows creatinine, and eGFR is worked out from it. This does the same sum the lab does, and explains the category in plain words.

Your details

Creatinine 80 µmol/L (0.90 mg/dL), age 50, female

G2: mildly reduced

eGFR, ml/min/1.73 m²74.1
CategoryG2 (mildly reduced)
EquationCKD-EPI 2009, no ethnicity adjustment (as UK labs use)
Creatinine in the other unit0.90 mg/dL

Results of 60 or more are hard to estimate precisely, and on their own do not mean kidney disease. Kidney disease is only diagnosed alongside a urine test or other signs of damage, over at least 3 months. Very muscly bodies, amputations and pregnancy all make the estimate less reliable.

If a result worries you, ask your GP surgery or practice nurse to talk it through. Call 111 if you feel unwell and are not sure what to do.

The working

Creatinine 80, a woman of 50

80 µmol/L ÷ 88.4 = 0.905 mg/dL. CKD-EPI 2009 for women uses 141 x (0.905 ÷ 0.7)^−1.209 x 0.993⁵⁰ x 1.018, because 0.905 is above 0.7. That comes to 74, category G2. Labs show anything above 90 as "over 90", because the estimate gets less precise up there.

The categories

G1 to G5

Category	eGFR	In words
G1	90 or more	normal or high
G2	60 to 89	mildly reduced
G3a	45 to 59	mildly to moderately reduced
G3b	30 to 44	moderately to severely reduced
G4	15 to 29	severely reduced
G5	under 15	kidney failure range

G1 and G2 only count as kidney disease if there are other signs of damage, such as protein in the urine.

Why this equation

CKD-EPI 2009, not 2021

NICE asks UK labs to use CKD-EPI without the old ethnicity adjustment, and the UK Kidney Association says the 2009 version should be used because the 2021 version has not been validated in UK people. US calculators often use 2021, which is why their answers can differ slightly from your report.

Read with care

What this cannot tell you

An estimate from one blood test, with known blind spots.

Work in pregnancy or for childrenBoth need different approaches.
Allow for muscleBodybuilders read low, people with little muscle or an amputation read high.
Diagnose kidney diseaseThat needs repeat tests over 3 months and a urine test.

Questions

Common questions

What is a normal eGFR?

90 or more is normal. 60 to 89 is common as people get older and is not kidney disease on its own.

Does eating meat affect eGFR?

It can. NICE advises not eating meat in the 12 hours before an eGFR blood test.

My eGFR is under 60, what now?

A first result under 60 is usually repeated within 2 weeks. It only counts as kidney disease if it stays under 60 for at least 3 months.

Why is there no ethnicity box?

The old ethnicity adjustment was found to overestimate kidney function in Black people in the UK, so NICE and the UK Kidney Association say not to use it.

Sources

Last checked 21 October 2026. Spotted something wrong? Tell us and we will fix it.

Talk your results through

If a result worries you, book a chat with your GP or practice nurse, or ask a pharmacist. Call NHS 111 if you feel unwell and are not sure what to do, and 999 in an emergency.