Buying guide
Best Research Peptide Vendors, Ranked on Lab Evidence
Ranked on what each vendor can prove: the third-party certificates it publishes, the laboratory that signed them, and the gap between the mass on the label and the mass in the vial.
58 vendors scored · 678 certificate records read · last updated 25 Sept 2026
The top-rated research peptide vendor is Next Gen Peptides, scoring 93.8 of 100 on 49 third-party certificates of analysis from ILS Laboratories. Below are the 10 highest-scoring vendors of 58 indexed, ranked by one published rubric over 678 lot-level certificate records. Every figure links to the document behind it.
Why trust this ranking
- PepIndex does not sell peptides. It has no product, no stock and no house brand.
- Scores come from a rubric published in full and are recomputable from the open dataset. Every data point carries its source URL and the date it was checked.
- Some outbound links are partner links and are marked as such. Partner status cannot reach the scoring function; the code will not compile if it is passed. How this is funded.
- 28 of 58 vendors publish a certificate this index could read, and 11 name a laboratory with recorded ISO/IEC 17025 accreditation. Both figures are lower than the marketing in this market implies.
The top 10, compared
| # | Vendor | Score | Testing laboratory | COAs | ISO 17025 | BPC-157 $/mg |
|---|---|---|---|---|---|---|
| 1 | Next Gen Peptides | 93.8 Extensively documented | ILS Laboratories | 49 | Yes | $3.00 |
| 2 | Amino Club | 88.3 Extensively documented | ILS Laboratories | 6 | Yes | $4.00 |
| 3 | Modern Aminos | 88.1 Extensively documented | Vanguard Laboratory | 30 | Yes | $6.80 |
| 4 | Bench Grade Peptides | 86.8 Extensively documented | AV Analytics | 53 | Not recorded | $3.90 |
| 5 | Ascend Science | 86.7 Extensively documented | Kovera Labs and/or ILS Labs | 27 | Yes | $4.90 |
| 6 | Polaris Peptides | 86.6 Extensively documented | Anthony Burke PhD Lab | 50 | Yes | $6.00 |
| 7 | Hydro Research Peptides | 86.5 Extensively documented | ILS Laboratories | 24 | Yes | $4.00 |
| 8 | PeptidePlugs | 86.3 Extensively documented | Freedom Diagnostics Testing | 103 | Not recorded | $3.00 |
| 9 | Origin Labs | 85.7 Extensively documented | Freedom Diagnostics Testing | 24 | Not recorded | $3.00 |
| 10 | Simple Peptide | 84.5 Well documented | White Lyophilized Powder Analytical | 28 | Not recorded | $5.50 |
The full board of 58 vendors, with filters, is on the vendor rankings page, and every captured price is on the price index.
Best for
Best overall
Highest score in the index at 93.8 of 100, on 49 certificates.
Best value
Cheapest basket of any priced vendor, at 40% of the peer median.
Most certificates
103 lot-level certificates on file, the largest published set in the index.
Best for GLP-1 compounds
The highest-ranked vendor that both publishes certificates for and prices retatrutide, tirzepatide or semaglutide.
Why each vendor ranks where it does
1.Next Gen Peptides
93.8Extensively documentedNext Gen Peptides ranks 1 of the index on 93.8 of 100, computed from 97% data coverage. 49 lot-level certificates are on file, issued by ILS Laboratories, and the assayed mass sits a mean 8.1% from the label. The testing laboratory holds ISO/IEC 17025 accreditation. Its basket prices at 58% of the peer median, so below the market. 25 tracked compounds are carried. The clearest gap on the record: no physical postal address is published.
2.Amino Club
88.3Extensively documentedAmino Club ranks 2 of the index on 88.3 of 100, computed from 95% data coverage. 6 lot-level certificates are on file, issued by ILS Laboratories, and the assayed mass sits a mean 10.9% from the label. The testing laboratory holds ISO/IEC 17025 accreditation. Its basket prices at 76% of the peer median, so below the market. 33 tracked compounds are carried. The clearest gap on the record: certificates are behind a self-attestation age gate — reachable in one click, but invisible to crawlers and to anyone unwilling to attest.
3.Modern Aminos
88.1Extensively documentedModern Aminos ranks 3 of the index on 88.1 of 100, computed from 100% data coverage. 30 lot-level certificates are on file, issued by Vanguard Laboratory, and the assayed mass sits a mean 12.3% from the label. The testing laboratory holds ISO/IEC 17025 accreditation. Its basket prices at 95% of the peer median, so below the market. 38 tracked compounds are carried. The clearest gap on the record: certificates are gated rather than openly readable.
4.Bench Grade Peptides
86.8Extensively documentedBench Grade Peptides ranks 4 of the index on 86.8 of 100, computed from 91% data coverage. 53 lot-level certificates are on file, issued by AV Analytics, and the assayed mass sits a mean 6.8% from the label. No accreditation is recorded for the testing laboratory. Its basket prices at 100% of the peer median, so above the market. 37 tracked compounds are carried. The clearest gap on the record: no iso/iec 17025 accreditation recorded for the testing lab.
5.Ascend Science
86.7Extensively documentedAscend Science ranks 5 of the index on 86.7 of 100, computed from 91% data coverage. 27 lot-level certificates are on file, issued by Kovera Labs and/or ILS Labs, and the assayed mass sits a mean 25.5% from the label. The testing laboratory holds ISO/IEC 17025 accreditation. Its basket prices at 83% of the peer median, so below the market. 33 tracked compounds are carried. The clearest gap on the record: no registered legal entity is disclosed.
6.Polaris Peptides
86.6Extensively documentedPolaris Peptides ranks 6 of the index on 86.6 of 100, computed from 97% data coverage. 50 lot-level certificates are on file, issued by Anthony Burke PhD Lab, and the assayed mass sits a mean 17.5% from the label. The testing laboratory holds ISO/IEC 17025 accreditation. Its basket prices at 96% of the peer median, so below the market. 32 tracked compounds are carried. The clearest gap on the record: no independent third-party reviews located.
7.Hydro Research Peptides
86.5Extensively documentedHydro Research Peptides ranks 7 of the index on 86.5 of 100, computed from 89% data coverage. 24 lot-level certificates are on file, issued by ILS Laboratories, and the assayed mass sits a mean 9.6% from the label. The testing laboratory holds ISO/IEC 17025 accreditation. Its basket prices at 73% of the peer median, so below the market. 16 tracked compounds are carried. The clearest gap on the record: no registered legal entity is disclosed.
8.PeptidePlugs
86.3Extensively documentedPeptidePlugs ranks 8 of the index on 86.3 of 100, computed from 90% data coverage. 103 lot-level certificates are on file, issued by Freedom Diagnostics Testing, and the assayed mass sits a mean 10.6% from the label. No accreditation is recorded for the testing laboratory. Its basket prices at 82% of the peer median, so below the market. 38 tracked compounds are carried. The clearest gap on the record: no iso/iec 17025 accreditation recorded for the testing lab.
9.Origin Labs
85.7Extensively documentedOrigin Labs ranks 9 of the index on 85.7 of 100, computed from 87% data coverage. 24 lot-level certificates are on file, issued by Freedom Diagnostics Testing, and the assayed mass sits a mean 17.0% from the label. No accreditation is recorded for the testing laboratory. Its basket prices at 82% of the peer median, so below the market. 20 tracked compounds are carried. The clearest gap on the record: no iso/iec 17025 accreditation recorded for the testing lab.
10.Simple Peptide
84.5Well documentedSimple Peptide ranks 10 of the index on 84.5 of 100, computed from 89% data coverage. 28 lot-level certificates are on file, issued by White Lyophilized Powder Analytical, and the assayed mass sits a mean 14.7% from the label. No accreditation is recorded for the testing laboratory. Its basket prices at 98% of the peer median, so below the market. 34 tracked compounds are carried. The clearest gap on the record: no iso/iec 17025 accreditation recorded for the testing lab.
Withdrawn from the index
Vendors removed from the board after they were listed, for going dark, withdrawing their documentation or failing a re-check. They are named here because a buying guide that only lists the living is not a record.
- Just a moment...3 Aug 2026
- Site Title3 Aug 2026
- SKO Compounds3 Aug 2026
- Error 403 Forbidden1 Aug 2026
- Error 403 Forbidden1 Aug 2026
- Maintenance1 Aug 2026
- purerawz1 Aug 2026
- rcs research1 Aug 2026
- Skye Peptides1 Aug 2026
Questions
- How do you decide which peptide vendor is best?
- Every vendor is scored 0–100 by one published rubric, version 1.10.0, over sourced facts: the certificates it publishes, the laboratory that signed them, the gap between labeled and assayed mass, its business transparency, its price against the peer median, and its enforcement record. The score is a pure function of the recorded data, so anyone can recompute it. Nothing is editorial, and no vendor can pay to move.
- How can I tell if a peptide vendor is legitimate?
- Ask for the certificate of the exact lot you were shipped, and check three things on it: a named third-party laboratory that is not the vendor, an assayed mass printed against the label claim rather than purity alone, and a lot number that matches the vial. A purity percentage with no laboratory, no lot and no mass is not evidence. Of the 58 vendors indexed here, 28 publish a certificate this index could read.
- What does ISO/IEC 17025 accreditation mean on a peptide COA?
- ISO/IEC 17025 is an accreditation of the testing laboratory's competence for a stated scope, granted by a recognised body. It says the laboratory has been audited; it does not say the vial is good. Most peptide testing laboratories are not accredited: 11 of the 58 vendors here name a laboratory with recorded accreditation.
- Does PepIndex test the peptides itself?
- No. PepIndex reads the certificates vendors publish, 678 lot records so far, and assesses the documentation and the laboratory behind them. It does not assay vials, and it says so rather than implying otherwise. Where an assay was independently commissioned, the record says so.
- How often do these rankings update?
- Vendor records are re-verified on a rolling basis and any field older than 90 days is flagged as stale on the profile. Scores recompute whenever the underlying data changes. This page was last updated 25 Sept 2026.
- Are these rankings affiliate-driven?
- No. Some outbound links are partner links and are marked as such. Partner status is structurally excluded from the scoring code: the function that computes a score cannot receive the affiliate field, so a commercial arrangement cannot move a rank even by accident.
- What happened to vendors that used to be listed?
- 9 vendors have been withdrawn from the index since it launched, for going dark, dropping their documentation or failing a re-check. They are named below with the date each was withdrawn.
Latest data report · 16 Sept 2026
Peptide COA report, September 2026: what 600+ certificates show
Data from 600+ peptide certificates of analysis: median purity, how often the vial matches its label, which labs test, and a five-step check for any COA.
Read the September 2026 peptide COA report →Last updated 25 Sept 2026, the most recent re-verification in the index. This page is generated from the live record, so the table and the writeups change when the data does and not on a schedule. Research use only: PepIndex publishes no dosing information and no protocols.