How is egfr (kidney function) calculated?

The eGFR (Kidney Function) Calculator substitutes your inputs (Serum creatinine, Age) into the standard expression: eGFR = 142 × min(Serum creatinine ÷ 0.7, 1)^(-0.241) × max(Serum creatinine ÷ 0.7, 1)^(-1.2) × (0.9938^Age). Every variable is read straight from the fields on this page, and the result is computed the moment you enter the values.

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   Step 1

   Enter your weight, height, and age as required.

2. 2

   Step 2

   Then press "Calculate" to get the result.

3. 3

   Step 3

   Review the result and details below before relying on it.

4. 4

   Step 4

   The breakdown lists your inputs — Serum creatinine, Age next to the value computed by eGFR = 142 × min(Serum creatinine ÷ 0.7, 1)^(-0.241) × max(Serum creatinine ÷ 0.7, 1)^(-1.2) × (0.9938^Age); read it before relying on the number.

5. 5

   Step 5

   Adjust one input at a time and compare scenarios: change Serum creatinine and re-run to see which variable moves the egfr (kidney function) result most.

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  The eGFR (Kidney Function) Calculator needs every variable in consistent units — Serum creatinine, Age — before the standard formula returns a valid result, so check each field's unit before entering values copied from elsewhere.

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  Read implausible results with suspicion: if the eGFR (Kidney Function) output sits orders of magnitude away from your expectation, re-read the inputs — a misplaced decimal or two swapped fields explains most nonsensical answers.

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  Round only at the end: eGFR (Kidney Function) carries full precision internally, so rounding intermediate values by hand can shift the final answer more than the accuracy of the formula itself ever would.

• Serum creatinine and Age must be entered in one consistent unit system: months against years skews the eGFR (Kidney Function) result silently. Convert every input to the unit named on its field first.

• Zero and negatives can sit outside the formula's domain: zero age may make the eGFR (Kidney Function) undefined, and a negative serum creatinine still returns a number. Check each input is inside the range the quantity allows.