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Coastal Peptides vs Zen Peptides
Head-to-head on 6 shared peptides: Coastal Peptides is cheaper on 0, Zen Peptides on 6. Average price gap 79% — compared Oct 19, 2026.
- Catalog
- 15 peptides
- In stock (shared)
- 6
- Last checked
- Sep 28, 2026(stale · 28d old)
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- Catalog
- 6 peptides
- In stock (shared)
- 6
- Last checked
- Oct 19, 2026(stale · 7d old)
Some outbound links are affiliate links — we may earn a commission on purchases made through them. It never affects rankings, prices, or purity data. How we make money
Price comparison — 6 shared peptides
Prices last checked Oct 19, 2026| Peptide | Coastal Peptides | Zen Peptides | Δ $/mg |
|---|---|---|---|
| AOD-9604 | $7.80/mg 5mg · $39.00 | $2.80/mgcheaper 50mg · $140.00 | 64% |
| KLOW | $1.49/mg 80mg · $119.00 | $0.33/mgcheaper 800mg · $265.00 | 78% |
| Retatrutide | $5.97/mg 30mg · $179.00 | $0.93/mgcheaper 300mg · $280.00 | 84% |
| Semaglutide | $7.90/mg 10mg · $79.00 | $0.53/mgcheaper 300mg · $160.00 | 93% |
| Tesamorelin | $6.50/mg 10mg · $65.00 | $2.45/mgcheaper 200mg · $490.00 | 62% |
| Tirzepatide | $3.98/mg 60mg · $239.00 | $0.41/mgcheaper 600mg · $245.00 | 90% |
Best available size tier per vendor, normalized to $/mg; in-stock tiers preferred. How prices are collected →
Third-party purity data
| Peptide | Coastal Peptides | Zen Peptides |
|---|---|---|
| GHK-Cu | 99.9%APeptigrity | 100.0%AFinnrick |
| Retatrutide | 99.8%AFinnrick | 99.5%AFinnrick |
| Tesamorelin | 99.5%APeptigrity | 96.9%BFinnrick |
| Tirzepatide | 99.9%AFinnrick | 99.8%AFinnrick |
On file: Coastal Peptides — 9 results (Finnrick ×5 · Peptigrity ×4) · Zen Peptides — 4 results (Finnrick ×4).
Common questions
Is Coastal Peptides or Zen Peptides cheaper?
Across 6 peptides both vendors sell, Coastal Peptides has the lower $/mg price on 0 and Zen Peptides on 6. The average per-peptide price gap is 79%. The table above compares each vendor's best size tier on a $/mg basis.
Do Coastal Peptides and Zen Peptides have third-party lab tests?
Coastal Peptides has 9 third-party results on file (Finnrick ×5 · Peptigrity ×4); Zen Peptides has 4 (Finnrick ×4). Independent labs test samples bought from vendors and publish HPLC purity — grade A (≥98%) is the research-use baseline.
How many peptides do Coastal Peptides and Zen Peptides both sell?
Both vendors list 6 of the same peptides, including AOD-9604, KLOW, Retatrutide, Semaglutide, Tesamorelin and 1 more. Coastal Peptides tracks 15 peptides total on PepVendors; Zen Peptides tracks 6.