eGFR Calculator (CKD-EPI 2021) & Creatinine Clearance
Calculate estimated glomerular filtration rate using the latest CKD-EPI 2021 (race-free) formula and creatinine clearance via Cockcroft-Gault. Essential for renal dose adjustment.
Stop opening a new tab for renal dosing checks
EasyClinic flags renal dose adjustments automatically the moment you prescribe NSAIDs, antibiotics, or ACE inhibitors to elderly or CKD patients. Built-in safety net.
Also Known As
eGFR vs Creatinine Clearance — Which to Use?
eGFR (CKD-EPI 2021) is the standard for diagnosing and staging chronic kidney disease (CKD). The 2021 update removed the controversial race coefficient and is now the international standard endorsed by NKF, ASN, KDIGO, and the Indian Society of Nephrology.
Creatinine Clearance (Cockcroft-Gault) is preferred for drug dose adjustment because most pharmacology references and FDA labels still use CrCl as the basis for renal dosing recommendations. This calculator gives you both.
When Renal Dosing Adjustment Is Critical
Failure to adjust drug doses in patients with reduced kidney function is one of the most common causes of preventable adverse drug events in elderly Indian patients. Drugs requiring renal adjustment include:
- Antibiotics: Vancomycin, aminoglycosides (gentamicin, amikacin), beta-lactams, fluoroquinolones, TMP-SMX, nitrofurantoin (avoid if eGFR <30)
- Antidiabetics: Metformin (avoid if eGFR <30), SGLT2 inhibitors, sulfonylureas
- Cardiovascular: Digoxin, ACE inhibitors, ARBs, spironolactone, LMWH (enoxaparin)
- Pain: NSAIDs (avoid in CKD), gabapentin, pregabalin, morphine
- Anticoagulants: DOACs (apixaban, rivaroxaban, dabigatran)
CKD Staging by eGFR (KDIGO)
| Stage | eGFR | Description |
|---|---|---|
| G1 | ≥90 | Normal — only CKD if other markers |
| G2 | 60-89 | Mildly decreased |
| G3a | 45-59 | Mild-moderate |
| G3b | 30-44 | Moderate-severe |
| G4 | 15-29 | Severe — refer nephrology |
| G5 | <15 | Kidney failure — dialysis/transplant |
Frequently Asked Questions
▸What is the difference between eGFR and creatinine clearance?
eGFR is an estimate of true GFR derived from serum creatinine using equations like CKD-EPI. CrCl is calculated using Cockcroft-Gault and includes weight. eGFR is preferred for CKD staging; CrCl is preferred for drug dosing.
▸Why was race removed from CKD-EPI in 2021?
Because using race as a biological factor was scientifically unjustified and contributed to delayed care for Black patients. The 2021 race-free equation gives more equitable kidney function estimates.
▸When should I refer a patient to a nephrologist?
Refer if eGFR <30 (Stage G4-G5), persistent proteinuria, rapidly declining GFR, refractory hypertension, suspicion of glomerular disease, or genetic kidney disease.
▸Can creatinine be normal but kidney function still impaired?
Yes — in elderly patients, those with low muscle mass, malnutrition, or amputees, "normal" creatinine can mask significant kidney impairment. Always calculate eGFR.
▸Should metformin be stopped in CKD?
Per ADA and KDIGO 2024 guidelines: Continue metformin if eGFR ≥45 (no dose change). Reduce dose if eGFR 30-44 and monitor closely. Discontinue if eGFR <30.
References
- Inker LA et al. New Creatinine- and Cystatin C-Based Equations to Estimate GFR without Race. NEJM 2021;385:1737
- Cockcroft DW, Gault MH. Prediction of creatinine clearance from serum creatinine. Nephron 1976;16(1):31-41
- KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of CKD
- ICMR Guidelines on Chronic Kidney Disease (India)
Tired of opening a new tab for this?
EasyClinic flags renal dose adjustments automatically the moment you prescribe NSAIDs, antibiotics, or ACE inhibitors to elderly or CKD patients. Built-in safety check.