Kidney function education
Kidney Failure Risk Calculator: 4-Variable KFRE
Estimate 2-year and 5-year risk of treated kidney failure in adults with established CKD and eGFR below 60.
Not for children, people without established CKD, eGFR ≥60, or rapidly changing kidney function. The percentage alone cannot determine referral, transplant assessment or dialysis, and this tool does not invent low/medium/high risk categories.
Method and equation
The four-variable Tangri model uses age, sex, eGFR and urine albumin-to-creatinine ratio (uACR). This implementation uses the original 2011 North American calibration: baseline survival 0.9750 at two years and 0.9240 at five years. ACR in mg/mmol is multiplied by 8.84 to obtain mg/g. The modeled outcome is dialysis or kidney transplantation, not merely a lower eGFR.
How to use this tool
- Confirm an established adult CKD diagnosis and stable eGFR below 60. Enter recent eGFR and quantitative urine ACR, choosing the unit printed on the report. A urine protein-to-creatinine ratio is not a substitute for urine ACR.
- Review the original report, earlier results and relevant urine tests with a qualified clinician before making a care decision.
Worked example
For age 55, male, eGFR 30 and ACR 300 mg/g, this calibration gives approximately 9.6% at two years and 27.0% at five years. An ACR of about 33.94 mg/mmol is equivalent.
Understanding the result
The percentage is a population-model probability, not an individual guarantee or a countdown to dialysis. Calibration differs across countries and care settings; a clinician may use a locally validated model or clinical pathway.
Limitations and safety
- Not for children, people without established CKD, eGFR ≥60, or rapidly changing kidney function. The percentage alone cannot determine referral, transplant assessment or dialysis, and this tool does not invent low/medium/high risk categories.
- Educational use only. A result cannot diagnose disease or choose a medicine dose. Do not delay urgent care for symptoms or rapidly changing kidney results.
Sources
Method and explanations checked against the sources below on October 14, 2026. This is editorial and technical verification, not a physician review. External sources may be in English.