Measure consistently
Use laboratory-reported creatinine units carefully and enter cystatin C only when measured. Height and weight de-indexing is informational and must not drive medication dosing here.
Race-free adult kidney-function estimate
Use current CKD-EPI equations and keep diagnosis out of one result.
Calculate 2021 creatinine eGFR, optional combined creatinine–cystatin C and cystatin-only estimates, G/A categories, method spread and informational de-indexing.
The calculation runs locally in this browser. Educational outputs do not replace professional assessment, diagnosis, treatment or emergency care.
Method and interpretation guide
Use the eGFR result as a transparent estimate
Use laboratory-reported creatinine units carefully and enter cystatin C only when measured. Height and weight de-indexing is informational and must not drive medication dosing here. The worksheet exposes its assumptions so the result can be checked instead of accepted as a black box.
Read the assumptions
The 2021 CKD-EPI equations are race-free population estimates. CKD requires an abnormality persisting at least three months or other evidence of kidney damage; G1 or G2 alone does not establish CKD.
Escalate important decisions
A calculator cannot examine symptoms, medical history, medication effects or measurement quality. Use qualified professional guidance when the decision has health consequences.
Local calculation
Inputs are processed in this browser. No account or external calculator is required to produce the result.
False precision
Extra decimal places do not remove biological variation, input error or limits in the underlying population equation.
Scope
The 2021 CKD-EPI equations are race-free population estimates. CKD requires an abnormality persisting at least three months or other evidence of kidney damage; G1 or G2 alone does not establish CKD.
Simple by design
Three steps to a clearer number.
Enter your details
Use realistic values in each field. You can change them anytime.
Calculate instantly
The formula runs locally, so there is no account or waiting time.
Use the result
Treat the answer as a practical estimate for your next decision.