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Renal Function

CrCl & GFR calculator.

Renal function drives dosing across antibiotics, anticoagulants, oncology medications, and specialty IV therapies. This command-center calculator compares Cockcroft-Gault, CKD-EPI 2021, Jelliffe, and measured GFR side-by-side so pharmacists can see the dosing impact clearly.

The problem: Which formula is "right"?

Cockcroft-Gault (1976) has been the dosing standard for decades, but it overestimates GFR in modern populations. CKD-EPI 2021 is more accurate — but it has variants: indexed vs. de-indexed, and the 2021 version removed the race coefficient. Different institutions use different formulas, and a single patient's "CrCl" can be 20–40% different depending on which formula you choose.

You can't just pick one. Your pharmacy protocol defines which formula to use for dosing decisions.

All formulas, side-by-side

Cockcroft-Gault (Actual, Ideal, Adjusted Body Weight)

The classic formula, still widely used despite known overestimation. Variants use actual, ideal, or adjusted body weight depending on patient BMI.

CKD-EPI 2021 (Race-Free)

The current KDIGO standard. Removes the race coefficient and provides better accuracy across populations. De-indexed and indexed variants available.

Jelliffe Formula

Alternative formula sometimes used in institutions with specific protocols or patient populations.

Measured GFR

Direct input of measured glomerular filtration rate (from iohexol clearance, EDTA scan, or cystatin C). Gold standard when available.

Why see all of them?

  • ✓Understand the range. See how much a single patient's CrCl varies across formulas. This helps you spot outliers and decide which formula is most appropriate.
  • ✓Compare to your protocol. Your pharmacy uses a specific formula for dosing. Use this calculator to confirm which one and see how the others differ.
  • ✓Audit dosing decisions. If a prescriber used a different formula than your standard, you can see it immediately and escalate if needed.
  • ✓No calculator limitations. Legacy calculators compute only one formula. This one is built for modern oncology pharmacy, where formula choice is a deliberate decision.
Try the CrCl calculator
Sign in to compare formulas and understand your institution's renal function dosing protocol.
Infu-IQ · Clinical workflow support tool
Final decisions follow institutional policy, product labeling, and pharmacist judgment. All formulas are supported by clinical literature and KDIGO guidance.