GFR Calculator

The estimated Glomerular Filtration Rate (eGFR) measures how well the kidneys filter waste from the blood. It is calculated from serum creatinine, age, and sex using the CKD-EPI 2021 equation (race-free version)

The calculator uses the standard published formula for gfr. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.

This calculator works with inches, square metres. You can enter values in the units shown — the calculator handles all conversions internally.

The core formula is: CKD-EPI 2021: eGFR = 142 × min(Scr/κ, 1)^α × max(Scr/κ, 1)^(−1.200) × 0.9938^Age × (1.012 if female). Each step in the calculation is shown so you can verify the result manually.