A $30 listing can cost more than a $45 listing once vial size, number of vials, form, and shipping are considered. PepGrades keeps offers in separate comparison groups so unlike products do not get ranked together.
Match the compound and form.
A lyophilized vial, nasal preparation, capsule, and topical product are not interchangeable price observations. They stay in separate groups even when the compound name is the same.
Match the amount and package.
Two 5 mg vials are a different purchase from one 10 mg vial. Both contain 10 mg in total, but the package may matter to the buyer and the listings should remain clear about what is actually sold.
Normalize only what the listing supports.
When the amount and price are clear, PepGrades can show simple figures such as dollars per milligram. If a listing is ambiguous, it should not be forced into a calculation.
Price comes after the trust floor.
The lowest-price role is chosen only among vendors that meet the current evidence requirements. A cheap listing does not erase missing testing or transparency information.
Prices are observations, not promises.
Stock, promotions, shipping, and listings change. Every comparison belongs to the observation time shown with the data, and the displayed price may have changed since that check.