Copper. Zinc.
The context between.
Serum copper and zinc can be compared as a dimensionless Cu/Zn ratio when their units match. Estimated non-ceruloplasmin-bound copper subtracts an assumed ceruloplasmin-bound fraction from total serum copper. This calculator shows the arithmetic and source assumptions; the estimate is assay-dependent and is not a direct free-copper measurement or a diagnosis.
Roberts & Schilsky, 2008, Hepatology 47:2089–2111 Twomey et al., 2007, Gut 56:154
01 / YOUR INPUTS
Start with the report.
Use the displayed units. Results from different specimens or methods need their own context.
Your entries stay in this browser. They are not attached to waitlist submissions. Download or copy a scorecard only when you choose.
02 / THE COMPARISON
The number,
with its context.
Enter or select the information on the left to see a source-labeled comparison.
The result will retain the units, source and limits relevant to this comparison.
THE ARITHMETIC
An estimate.
Not a measurement.
Cu/Zn divides the two measurements after matching units. Estimated non-ceruloplasmin-bound copper (NCC) subtracts an assumed ceruloplasmin-bound fraction from total copper.
Cu/Zn = serum copper (µg/dL) ÷ serum zinc (µg/dL)
Estimated non-ceruloplasmin-bound copper (µg/dL) = total serum copper (µg/dL) − 3.15 × ceruloplasmin (mg/dL)
Estimated NCC % = estimated NCC ÷ total serum copper ×100
Calculated NCC depends on both assays and can be negative when ceruloplasmin is overestimated. NCC includes copper associated with other molecules and is not a direct measure of unbound ionic copper. Do not clamp a negative estimate to0 or classify it as optimal; show that it cannot be interpreted.
The 0.8–1.2 Cu/Zn reference criterion in Walsh’s 2004 cohort belongs to that historical study. Its serum copper and plasma zinc context is distinct from a universal serum-pair target. This tool does not assign a universal “free copper below 15%” goal.
Roberts & Schilsky, 2008, Hepatology 47:2089–2111 · Twomey et al., 2007, Gut 56:154
READ THE ORIGINALS
Sources, within reach.
- Roberts & Schilsky, 2008, Hepatology 47:2089–2111Historical AASLD clinical guideline; not the current Wilson guidance
- Twomey et al., 2007, Gut 56:154Authors report assay limitations and physiologically impossible negative calculated values
- Walsh, Glab & Haakenson, 2004, Physiology & Behavior 82:835–839Uncontrolled, individualized multicomponent intervention cohort; 207 patients, median age11.5
- Schilsky et al., 2023, Hepatology 77:1428–1455 (2022 guidance)Current AASLD guidance landing record; do not present an online calculator as its diagnostic pathway
§ 06 EARLY ACCESS
"In normal range" was
never really an answer.
Join the early-access waitlist and get instant access to our Orthomolecular Optimal vs. Standard Lab Reference Sheet.
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Your lab reference sheet is ready: ten markers, assay-specific ranges, primary sources and the limits of proposed optimal targets.
Download the reference sheet ↓STEP 01 / HELP SHAPE THE APP