GFR calculator

Estimate adult eGFR with the 2021 CKD-EPI creatinine equation, without a race coefficient.

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Serum creatinine (mg/dL)

Age (years)

More inputs and assumptions

Sex in the published equation

Answer

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Estimate adult eGFR with the 2021 CKD-EPI creatinine equation, without a race coefficient.

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Precision and calculation record

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Formula and assumptions

For adults with standardized serum creatinine and stable kidney function. Output is normalized to 1.73 square meters, not an absolute clearance or a drug dose. Creatinine-only estimates can be inaccurate with unusual muscle mass, acute illness or pregnancy. The combined creatinine-cystatin C equation is preferred when available. A clinician must interpret the result; a single value does not diagnose kidney disease.

Automatic precision shows numbers to 12 significant digits. Thousands separators such as 1,000 are accepted; use a dot for decimals.

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Updated 2026-09-29

Using GFR calculator

Estimate adult eGFR with the 2021 CKD-EPI creatinine equation, without a race coefficient.

Next: BSA calculator

Next: Calculate BMI

A worked example

A 50-year-old man with serum creatinine 1.0 mg/dL has an estimated GFR of about 92 mL/min/1.73 m².

Before you use the result

Example results for serum creatinine (mg/dl)

These examples use Age (years): 50; Sex in the published equation: Male. They are reference calculations, not recommended settings.

Serum creatinine (mg/dL)	Estimated GFR (mL/min/1.73 square meters)
0.5	124.259689
1	91.691479
2	39.911034

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ToolOctopus. “GFR calculator.” Updated 2026-09-29. https://tooloctopus.com/gfr-calculator.

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