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GFR Calculator

Estimate estimated gfr from serum creatinine, creatinine unit, adult equation with the GFR Calculator.

Choose an age groupUse CKD-EPI for adults or bedside Schwartz for children.
2 options
ESTIMATED GFR91.7 mL/min/1.73m²

2021 CKD-EPI adult equation; category G1. Race is not used in the current 2021 equation. Clinical interpretation requires history and urine testing. Educational estimate only; not medical advice.

Normalized creatinine
1.000 mg/dL
Equation
2021 CKD-EPI adult
Filtration category
G1
Estimate based on the values shown
Method2021 race-free or legacy 2009 CKD-EPI adult equations and bedside Schwartz pediatric equation; creatinine accepts mg/dL or µmol/L.

Before you use the result

Educational estimate only; it cannot diagnose a condition or replace advice from a qualified health professional.

Sources

EDITORIAL NOTES

Using the GFR Calculator responsibly

Page-specific guidance based on this calculator’s implemented method, inputs, and known limits.

What this result is useful for

Estimated glomerular filtration rate uses serum creatinine with the selected adult or pediatric equation to approximate kidney filtration. It is intended to help explain a reported estimate and its inputs, not to diagnose kidney disease or determine treatment.

Assumptions and limits

Creatinine-based equations can be less reliable with rapidly changing kidney function, unusual muscle mass, amputation, pregnancy, some diets or supplements, and at certain ages. Adult and pediatric formulas are not interchangeable, and laboratory units must be selected correctly.

How to check the result

Confirm the creatinine unit, age group, height when required, and equation version. A single estimate should be interpreted with trends, urine testing, clinical history, and the laboratory report. Discuss abnormal or changing results with a qualified clinician.

Content review: August 30, 2026
CALCULATOR GUIDE

How to use the GFR Calculator

Estimate estimated gfr from serum creatinine, creatinine unit, adult equation with the GFR Calculator. It includes Adults, Children workflows, so choose the one that matches the values you actually know. Use it to understand an educational estimate and the inputs behind it, not as a diagnosis or treatment decision.

Step by step

  1. For the GFR example, select Adults and enter serum creatinine, creatinine unit, adult equation, age, gender. Keep each value in the unit displayed beside its field.
  2. Review the selected GFR workflow and inputs, then read estimated gfr in the result panel.
  3. Change one GFR assumption at a time to compare scenarios. Use Reset to restore this tool's worked example values.

How the calculation works

2021 race-free or legacy 2009 CKD-EPI adult equations and bedside Schwartz pediatric equation; creatinine accepts mg/dL or µmol/L.

Worked example

To reproduce the GFR worked example, reset the calculator. Select the Adults workflow. Use serum creatinine 1; creatinine unit mg/dL; adult equation 2021 CKD-EPI (race-free); age 50 years; gender Male. The result is estimated gfr of 91.7 mL/min/1.73m². 2021 CKD-EPI adult equation. Review the displayed units before comparing the result.

Understanding the result

The GFR reports estimated gfr. Use it to understand an educational estimate and the inputs behind it, not as a diagnosis or treatment decision. Educational estimate only; it cannot diagnose a condition or replace advice from a qualified health professional.

How to check the answer

Check the GFR estimate by confirming the units and supported ranges for serum creatinine, creatinine unit, adult equation. Compare estimated gfr with another published method or direct measurement when available, and ask a clinician before using it for a health decision.

Common questions

What does the GFR calculate?

Estimate estimated gfr from serum creatinine, creatinine unit, adult equation with the GFR Calculator.

Which inputs does the GFR example use?

The worked example uses serum creatinine, creatinine unit, adult equation, age, gender in the Adults workflow. Other workflows can show different fields. Keep the chosen workflow and units with the result when comparing calculations.

Is the GFR result exact?

Educational estimate only; it cannot diagnose a condition or replace advice from a qualified health professional. Recheck serum creatinine, creatinine unit, adult equation and use estimated gfr only for a decision where that level of precision is appropriate.

Formula tests, limits, and sources reviewed September 1, 2026. Guide examples updated October 12, 2026.
INTERPRET THE RESULTRead the health guideCheck assumptions, limitations and comparison methods →
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