This calculator estimates glomerular filtration rate (eGFR) from serum creatinine. Adults (18+) get three side-by-side equations — IDMS-traceable MDRD, CKD-EPI 2009, and Mayo quadratic. Children (18 and under) use the bedside Schwartz formula from height and creatinine. Results are educational estimates, not a diagnosis or a substitute for a lab report.
Formula
Serum creatinine is converted to mg/dL (µmol/L ÷ 88.4). Height in inches is converted with 1 in = 2.54 cm. Displayed GFR is one decimal place.
IDMS-traceable MDRD (adults)
GFR = 175 × (SCr)^−1.154 × (age)^−0.203
× (0.742 if female) × (1.212 if Black)
CKD-EPI 2009 (adults)
Black female, SCr ≤ 0.7: 166 × (SCr/0.7)^−0.329 × 0.993^age
Black female, SCr > 0.7: 166 × (SCr/0.7)^−1.209 × 0.993^age
Black male, SCr ≤ 0.9: 163 × (SCr/0.9)^−0.411 × 0.993^age
Black male, SCr > 0.9: 163 × (SCr/0.9)^−1.209 × 0.993^age
Non-Black female, SCr ≤ 0.7: 144 × (SCr/0.7)^−0.329 × 0.993^age
Non-Black female, SCr > 0.7: 144 × (SCr/0.7)^−1.209 × 0.993^age
Non-Black male, SCr ≤ 0.9: 141 × (SCr/0.9)^−0.411 × 0.993^age
Non-Black male, SCr > 0.9: 141 × (SCr/0.9)^−1.209 × 0.993^age
Mayo quadratic (adults)
If SCr is below 0.8 mg/dL, 0.8 is used in its place.
GFR = e^(1.911 + 5.249/SCr − 2.114/SCr² − 0.00686 × age − (0.205 if female))
Schwartz / bedside CKiD (children)
GFR = 0.413 × height (cm) / SCr (mg/dL)
These equations estimate GFR from creatinine. Muscle mass, diet, extra creatinine secretion, and lab methods all move the number. Direct GFR (inulin clearance) is impractical for everyday care, so eGFR is the usual screen — not a diagnosis, and not a reason to change medicines on your own.
Population mean estimated GFR
| Age | Mean estimated GFR (mL/min/1.73 m²) |
|---|---|
| 20–29 | 116 |
| 30–39 | 107 |
| 40–49 | 99 |
| 50–59 | 93 |
| 60–69 | 85 |
| 70+ | 75 |
A BSA-adjusted GFR around 100–130 mL/min/1.73 m² in men and 90–120 in women under 40 is often quoted as the usual range. After 40 the mean falls with age.
Chronic kidney disease stages (by GFR)
| Stage | GFR (mL/min/1.73 m²) |
|---|---|
| Normal | 90+ and no proteinuria |
| CKD1 | 90+ with evidence of kidney damage |
| CKD2 (Mild) | 60 to 89 with evidence of kidney damage |
| CKD3 (Moderate) | 30 to 59 |
| CKD4 (Severe) | 15 to 29 |
| CKD5 Kidney failure | less than 15 |
A GFR above 60 is usually adequate on its own. CKD1 and CKD2 still need other evidence of kidney damage. This page cannot see that evidence, so the badge for 90+ is labeled “Normal or CKD1.”
Examples
Adult default: 0.9 mg/dL, age 50, male, not Black
MDRD is 89.3, CKD-EPI 99.2, and Mayo 120.3 mL/min/1.73 m². The CKD-EPI figure sits in the 90+ band. The same creatinine as 79.56 µmol/L gives the same three numbers.
Adult woman, same creatinine and age
MDRD is 66.3, CKD-EPI 74.8, and Mayo 98.0 mL/min/1.73 m². CKD-EPI lands in the CKD2 (mild) GFR range; that stage still needs other signs of kidney damage before it is a diagnosis.
Child default: 0.9 mg/dL, 110 cm
Schwartz is 50.5 mL/min/1.73 m². 43.3 inches is the same height to one decimal. Adult CKD bands are not applied on the Children tab.