GFR Calculator

Last updated: April 2026

Age

yrs

Sex

Serum creatinine

mg/dL

Creatinine unit

Estimated GFR

98 mL/min/1.73m^2

CKD stage: G1

Normal or high kidney filtration. Kidney damage markers may still matter.

Details

Creatinine used1 mg/dL

EquationCKD-EPI 2021 creatinine equation

Age40

Sexmale

Kappa / alpha0.9 / -0.302

Medical warning

This calculator estimates eGFR and is not a medical diagnosis. Kidney function should be interpreted by a healthcare professional, especially if results are low, changing, or accompanied by symptoms.

CKD staging usually requires repeat results and clinical context, including urine albumin and other findings.

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What is GFR?

GFR estimates how well the kidneys filter blood.

What is eGFR?

eGFR is estimated from blood creatinine, age, and sex.

How is eGFR calculated?

This calculator uses the CKD-EPI 2021 creatinine equation without a race coefficient.

What do GFR stages mean?

G1 is 90 or higher, G2 is 60 to 89, G3a is 45 to 59, G3b is 30 to 44, G4 is 15 to 29, and G5 is below 15.

Limitations of eGFR

eGFR is not a diagnosis by itself. It can be affected by muscle mass, diet, pregnancy, acute illness, and some medicines. CKD assessment often needs repeat tests and urine albumin.

What does this mean?

This calculator is designed to help you understand the likely number before you make a decision or start an application.

Your result should be checked against official UK guidance, especially if your circumstances include dependants, exemptions, prior leave, or a complex immigration history.

Treat the figure as a planning tool rather than legal advice. Where the answer affects an application deadline or major payment, speak to an authorised adviser.