Health / Browser calculator

GFR Calculator

GFR Calculator works from the inputs you provide and returns estimated gfr (ml/min/1.73 m²). Use the calculation panel to explore a scenario, then check the formula and limitations before applying the result.

Your inputs

Minimum: 0.1 · Maximum: 30
Minimum: 20 · Maximum: 120

Your results

Enter your values and calculate to see the result.

This calculator is for informational purposes only and is not a substitute for professional medical advice.

Formula and calculation method

2021 CKD-EPI creatinine: eGFR = 142 × min(Scr/k,1)^a × max(Scr/k,1)^−1.200 × 0.9938^age × sex factor. Female k=.7, a=−.241, factor=1.012; male k=.9, a=−.302, factor=1.

Adult creatinine estimate, without race adjustment. Not validated here for pregnancy, acute changes in kidney function or unusual muscle mass. A clinician must interpret kidney results.

How to use gfr calculator

  1. Set Serum creatinine (mg/dL). The example below uses 1.
  2. Set Age (years). The example below uses 30.
  3. Set Sex parameter used by equation by choosing the option that matches your calculation.
  4. Select Calculate to update the result. Reset restores the illustrated inputs. Copy, print or download your own result if you need a record.

Worked example

Example inputs
Serum creatinine (mg/dL)
1
Age (years)
30
Sex parameter used by equation
Male
Estimated GFR (mL/min/1.73 m²)
103.83628171

Factors affecting your result

Adult creatinine estimate, without race adjustment. Not validated here for pregnancy, acute changes in kidney function or unusual muscle mass. A clinician must interpret kidney results.

Changing serum creatinine (mg/dl) changes the scenario being evaluated. Adjust one input at a time when comparing results, keep a copy of the assumptions, and compare values using the same unit and period. A precise arithmetic result does not make an uncertain assumption precise.

Frequently asked questions

How does the gfr calculator work?

2021 CKD-EPI creatinine: eGFR = 142 × min(Scr/k,1)^a × max(Scr/k,1)^−1.200 × 0.9938^age × sex factor. Female k=.7, a=−.241, factor=1.012; male k=.9, a=−.302, factor=1.

What inputs does GFR Calculator need?

Enter serum creatinine (mg/dl), age (years), sex parameter used by equation. Choose values that correspond to the same situation and measurement convention.

How should I interpret the gfr calculator result?

Adult creatinine estimate, without race adjustment. Not validated here for pregnancy, acute changes in kidney function or unusual muscle mass. A clinician must interpret kidney results.

Are my gfr calculator inputs uploaded?

No. The calculation runs in this browser. Favorites, recent tool names, theme and formatting preferences may be saved locally, but calculation inputs are not sent to a calculation server or stored by this website. Shared links do not include entered values.

Method reference

Maintained by Calculators.buzz Editorial Team. Implementation date: . No professional credentials or clinical review are claimed. Read our methodology policy.