How we compare prices

Every ranking on Peptide Discount is computed from one number: the effective per-unit price. No vendor can pay to move up a list.

The math

• Normalize the size. Each listing is converted to a total quantity — milligrams for solids and capsules (kits multiply: a "10mg kit of 10 vials" is 100mg; "500mcg × 60 caps" is 30mg; liquids use concentration × volume), milliliters when no concentration is published.
• Apply the best coupon. We take the vendor's best currently-valid public code — percent or fixed amount, whichever discounts that specific listing more — and compute effective price = price − discount. Expired codes are never applied.
• Divide. Unit price = effective price ÷ normalized quantity, shown as $/mg (or $/ml). The lowest in-stock unit price wins "Best value."

Where the data comes from

Prices are collected automatically from each vendor's public catalog, respecting robots.txt, with an identifiable crawler. Every listing displays when it was last updated. Unclear listings are reviewed by a human before they are published — never guessed.

Testing & COA transparency

Where vendors publish third-party testing (certificates of analysis), we surface that status on each listing — tested, COA pending, or not tested — and link to the source where available. A testing badge reflects the vendor's published documentation; it is not our endorsement, and we independently verify nothing about product contents.

How we make money

Outbound links may carry an affiliate tag and coupon code; if you buy, the vendor pays us a commission at no extra cost to you. Commission rates differ across vendors but have no effect on ranking — the $/mg math above is the entire ranking.

Corrections

Spot a wrong price, dead coupon, or mismatched product? Report it and we'll fix it.