# eGFR Calculator (CKD-EPI 2021)

URL: https://speedycalculator.com/calculators/health/egfr/
Last updated: 2026-10-25

> The eGFR calculator estimates kidney function from serum creatinine, age and sex using the race-free CKD-EPI 2021 equation recommended by the U.S. National Kidney Foundation. It also gives the CKD stage.

## Inputs

- Sex
- Age (years)
- Serum creatinine (mg/dL, µmol/L)

## Results

- eGFR

## Formula

```
eGFR = 142 × min(Scr/κ, 1)^α × max(Scr/κ, 1)^−1.200 × 0.9938^age × 1.012 [female]
κ = 0.7 (F) / 0.9 (M),  α = −0.241 (F) / −0.302 (M)
```

## Explanation

Glomerular filtration rate measures how much blood the kidneys filter each minute. It is the main measure for staging chronic kidney disease.

### How to use the eGFR Calculator

- **Sex**
- **Age**
- **Serum creatinine**

Results update as you type, and every field accepts the units shown in its menu.

### How it works

Creatinine is scaled by a sex-specific constant, and the equation adjusts for age.

### Inputs explained

FieldWhat to enterSexChoose one: Male, FemaleAgeIn yearsSerum creatinineUnits: mg/dL, µmol/L

### Example values

How the main result changes when **Age** changes and everything else stays at the example values above:

Age (years)eGFR (mL/min/1.73 m²)27.59441.2586557968.757382.56711056
*Health note: this calculator is for education and screening only and is not a diagnosis or treatment advice. Discuss your results with a qualified clinician.*

## Worked example

Inputs — Sex: Male; Age: 55 years; Serum creatinine: 1.1 mg/dL.

Results — **eGFR = 79 mL/min/1.73 m²**.

## Key terms

- **GFR**: Glomerular filtration rate.

## FAQ

**Why was race removed?**
The 2021 equation dropped the race coefficient to avoid bias; it is now the recommended standard in the U.S.

**Does one result diagnose CKD?**
No, CKD requires reduced eGFR or kidney damage for at least three months.

**What formula does the eGFR Calculator use?**
eGFR = 142 × min(Scr/κ, 1)^α × max(Scr/κ, 1)^−1.200 × 0.9938^age × 1.012 [female].


## Sources

- [Inker LA et al. New creatinine- and cystatin C–based equations to estimate GFR without race. N Engl J Med, 2021](https://pubmed.ncbi.nlm.nih.gov/34554658/)