WE PICKED ONE.
THEN WE KEPT PICKING IT.
PEAK LAB
PEPTIDES
Shop through our link and we earn a small commission — at no cost to you. Our review pre-dates the partnership by six months, and the commission doesn't change what we wrote above.
Visit PEAK LAB ↗VERIFIED
2026
OUR 6-POINT CRITERIA.
Third-party HPLC ≥ 99% purity
Independent lab verification on every batch — not the supplier's own in-house lab.
COA on every batch, by lot
Certificate of Analysis tied to the specific lot number. Not a generic PDF reused across batches.
Cold chain from lab to door
Peptides shipped with ice packs in insulated packaging. We verified intact cold chain on all 12 test shipments.
Published sourcing protocol
Transparent about where API comes from, how it's stored, and how it's handled.
Responsive to researcher inquiries
Real answers to technical questions — not boilerplate "we cannot provide medical advice" brush-offs.
Re-tested quarterly, independently
We pull random batches quarterly and send them to our own HPLC lab. If a batch fails, they're out.
35+ compounds currently available.
Every peptide we profile that carries a “✓ AT PEAK LAB” badge in our library is currently stocked. That's most of the popular ones: BPC-157, TB-500, GHK-Cu, semaglutide, tirzepatide, retatrutide, CJC-1295, ipamorelin, tesamorelin, follistatin-344, cagrilintide, MOTS-c — plus the newer compounds like SLU-PP-332 and 5-Amino-1MQ.
Browse the library →PepGains has one affiliate partner: PEAK LAB PEPTIDES. When you purchase through our links, we earn a commission on the sale at no extra cost to you. Our editorial review of PEAK LAB pre-dates this partnership by six months. If they stopped meeting the 6-point criteria above, we would drop the partnership — we've done this with other suppliers before.