Kidney function check
eGFR calculator
eGFR (estimated glomerular filtration rate) is the number most labs use to describe how well your kidneys filter blood. It is calculated from a creatinine blood test, your age and your sex.
Your lab value
Creatinine is on a basic or comprehensive metabolic panel. Nothing you enter leaves this page.
What you will see
Your estimated GFR, its KDIGO stage (G1 to G5) and what that range usually means.
Educational only, not medical advice. One eGFR result cannot diagnose kidney disease.
Source
CKD-EPI 2021 creatinine equation without a race term: Inker LA et al., N Engl J Med 2021. Stages: KDIGO 2024 guideline.
Validated in
Adults 18 and older. Built and checked against measured kidney function in adults taking part in research studies (Inker 2021).
Limits
Creatinine depends on muscle as well as the kidneys, so the estimate can be off in people with very high or very low muscle mass, amputations, or a very high meat or creatine intake. Not for pregnancy, children or sudden (acute) kidney injury.
What eGFR numbers mean
NIDDK, part of the US National Institutes of Health, explains the main lines this way: an eGFR of 60 or more is in the normal range, less than 60 may mean kidney disease, and 15 or less is called kidney failure (NIDDK). Doctors also use the more detailed stages from the KDIGO guideline (KDIGO 2024):
| Stage | eGFR (mL/min/1.73 m²) | Description |
|---|---|---|
| G1 | 90 or more | Normal or high |
| G2 | 60 to 89 | Mildly decreased |
| G3a | 45 to 59 | Mildly to moderately decreased |
| G3b | 30 to 44 | Moderately to severely decreased |
| G4 | 15 to 29 | Severely decreased |
| G5 | Under 15 | Kidney failure |
A stage of G1 or G2 on its own does not mean kidney disease. KDIGO defines chronic kidney disease as a problem with kidney structure or function, such as an eGFR below 60 or albumin in the urine, that lasts more than 3 months (KDIGO 2024).
Why one low result is not a diagnosis
eGFR can dip for a short time, for example after dehydration, an illness or some medicines, and creatinine itself varies with muscle mass and diet (KDIGO 2024). That is why the guideline asks for the change to last more than 3 months before calling it chronic kidney disease (KDIGO 2024). If your result is below 60, the usual next step is to repeat the test and add a urine albumin test.
The other half: urine albumin
eGFR measures filtering. The urine albumin-to-creatinine ratio (UACR) looks for protein leaking into the urine, an early sign of kidney damage. NIDDK lists 30 mg/g or less as normal and more than 30 mg/g as a possible sign of kidney disease (NIDDK). Someone can have a normal eGFR and a raised UACR, so the two tests are read together (KDIGO 2024). How the two combine into one risk chart is in kidney disease stages, explained.
Who should have their kidneys checked
Kidney disease rarely causes symptoms early on. CDC estimates that about 14% of US adults, around 37 million people, have chronic kidney disease, and that about 9 in 10 adults with it do not know (CDC). NIDDK recommends getting checked if you have diabetes, high blood pressure, heart disease or a family history of kidney failure, and testing every year if you have diabetes (NIDDK).
About the equation
This calculator uses the CKD-EPI 2021 creatinine equation (Inker 2021). Earlier versions included a race term. The 2021 version was refit without it, so the same creatinine, age and sex always give the same result (Inker 2021). It is also the equation the AHA PREVENT model used, so the number here can go straight into our heart risk calculator.
Your lab report may show a slightly different number. Labs round creatinine differently, and some use a cystatin C test, which is less affected by muscle mass (KDIGO 2024).
Common questions
Is an eGFR of 60 normal?
An eGFR of 60 or more is in the normal range on NIDDK's scale (NIDDK). On the KDIGO stages, 60 to 89 is called mildly decreased, which is not kidney disease on its own unless there are other signs of kidney damage (KDIGO 2024).
What eGFR is stage 3 kidney disease?
Stage G3a is 45 to 59 and G3b is 30 to 44, when the result has stayed in that range for more than 3 months (KDIGO 2024).
Can I raise my eGFR?
That depends on the cause, and it is a question for your doctor. This page does not give treatment advice.
See also which numbers to ask your doctor for.
Sources
- Inker LA, Eneanya ND, Coresh J, et al. New Creatinine- and Cystatin C-Based Equations to Estimate GFR without Race. N Engl J Med. 2021;385:1737-1749. doi.org/10.1056/NEJMoa2102953
- Kidney Disease: Improving Global Outcomes (KDIGO) CKD Work Group. KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease. Kidney Int. 2024;105(4S):S117-S314. doi.org/10.1016/j.kint.2023.10.018
- National Institute of Diabetes and Digestive and Kidney Diseases (NIH). Chronic Kidney Disease Tests and Diagnosis. www.niddk.nih.gov/health-information/kidney-disease/chronic-kidney-disease-ckd/tests-diagnosis
- Centers for Disease Control and Prevention. Chronic Kidney Disease in the United States. www.cdc.gov/kidney-disease/php/data-research/index.html
Written and maintained by the uncovermyrisk.com editorial team. We do not have a medical reviewer; every claim links to its primary source above. Last reviewed: 2026-10-27. Spotted an error? See About.