Choose a context and solve for the Cu/Zn mass ratio, copper, or zinc. The tool converts matching mass units; intake, blood and hair ratios are not interchangeable. Results do not diagnose a condition or recommend supplement doses.

Same time period; use elemental copper and zinc amounts. A ratio does not determine a supplement dose.

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Example intake amounts

Examples are not dose recommendations.

Food amounts vary. Excess zinc can reduce copper absorption.

Copper Zinc Ratio Formula

The following formula is used to calculate the Copper Zinc Ratio. 

CZR = C / Z
  • Where CZR is the dimensionless copper-to-zinc mass ratio
  • C is the total copper ingested 
  • Z is the total zinc ingested 

To calculate the Cu/Zn mass ratio, divide copper by zinc after converting both to matching mass units. Use the same time period for intake, or the same specimen type and collection time for lab values. Molar ratios require separate atomic-weight conversion. The examples below are arithmetic examples, not intake recommendations.

How to Calculate Copper Zinc Ratio?

The following example problems outline how to calculate Copper Zinc Ratio.

Example Problem #1:

  1. First, determine the total copper ingested.
    • The hypothetical copper amount is given as 80 µg.
  2. Next, determine the total zinc ingested.
    • The hypothetical zinc amount is provided as 10 µg.
  3. Finally, calculate the Copper Zinc Ratio using the equation above: 

CZR = C / Z

The values given above are inserted into the equation below and the solution is calculated:

CZR = 80 / 10 = 8.00

Example Problem #2: 

For this problem, the variables required are provided below:

hypothetical copper amount = 100 µg

hypothetical zinc amount = 20 µg

Test your knowledge using the equation and check your answer with the calculator above.

CZR = C / Z = ?