What Is the Difference Between Peptide Purity and Potency?

They sound like the same thing.

They are not.

Purity asks how much of the detected material appears to be the intended peptide compared with related impurities.

Potency asks how much active peptide is actually present.

That difference matters because a vial can test at 99% purity and still contain less peptide than the label says.

Imagine ordering a bottle labeled 10 mg.

The material inside could be very pure—but there may only be 8 mg of it.

Clean product.

Wrong amount.

That is why a giant 99% PURE badge does not automatically prove the vial is accurately filled.

It may tell you the material tested cleanly.

It does not necessarily tell you how much was there.

This is one of the easiest distinctions for marketing to blur because most people see “99%” and assume every question has been answered.

It has not.

Purity tells you about the quality of the material detected.

Potency or assay tells you whether the amount matches what was claimed.

Both matter.

And when a company only talks about one, it is fair to wonder about the other.

All products are sold strictly for laboratory research purposes and are not intended for human consumption.