C-peptide unit converter
Convert the units on a C-peptide laboratory report. The result remains a C-peptide concentration.
Formula & units
C-peptide (nmol/L) = C-peptide (ng/mL) × 0.331
C-peptide in pmol/L equals ng/mL × 331. To convert back to ng/mL, divide nmol/L by 0.331.
Worked example
C-peptide 1.8 ng/mL = 0.596 nmol/L = 595.8 pmol/L.
What the result can tell you
There is no fixed concentration conversion from C-peptide to insulin. This tool does not generate HOMA1 or HOMA2 results from C-peptide.
Read the interpretation guide →
Sources for this method
Questions about C-peptide unit converter
Can I calculate HOMA-IR with C-peptide?
C-peptide cannot replace insulin in the HOMA1 equation. Oxford’s HOMA2 software supports C-peptide within its own model and documented conditions.
Source: Oxford HOMA calculator and FAQs (opens in a new tab) · Related calculator → · Link to answer
Can C-peptide be converted to insulin?
Not by a fixed concentration multiplier. Their handling and clearance differ, so a C-peptide unit conversion cannot produce an insulin concentration.
Source: Mayo Clinic Laboratories · C-peptide (opens in a new tab) · Related calculator → · Link to answer
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