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Diabetes & Blood Sugar

C-Peptide Test

A byproduct of insulin production. Reflects how much insulin your pancreas is making, not how much you've injected.

Physician reviewed
Results in 1–3 days
4,000+ lab locations

What is C-Peptide?

A byproduct of insulin production. Reflects how much insulin your pancreas is making, not how much you've injected.

C-Peptide Reference Range

These are the typical adult reference ranges used by major US labs. Your report will include the specific range used by the lab that processed your sample.

PopulationRange
age 18+1.10 – 4.40 ng/mL

Reference ranges are educational. Always interpret your result with the specific range printed on your lab report and discuss anything outside the range with a clinician.

Related Diabetes & Blood Sugar biomarkers

Markers commonly tested alongside C-Peptide.

Frequently asked

No. TestWell's licensed physician network reviews and approves your order — usually within minutes. You can place an order online without an in-person visit or a referral from your own doctor.

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