M-Peptides reviews
M-Peptides reviews: 24 independent lab tests across 2 products, with a mixed lab record.
Written by the Peptide Vendor Reviews editorial team
Is M-Peptides legit? Lab record: Mixed
How we rate- 24 independent tests
- 20 of 24 lots filled to label
- Median purity 99.82%
- 1 of 2 products graded D or E
Some of M-Peptides's products graded D or E. The shops below tested A or B for the same peptides.
Better-tested Retatrutide
M-Peptides graded E. Paradigm Peptide's Retatrutide graded A across 8 tests, $10.00 / mg.
Buy from Paradigm PeptideAll better-tested optionsPeptide Vendor Reviews independently tests products and verifies reviews. Public methodology, no pay-to-rank.
Better-tested options
Where M-Peptides graded D or E, these shops' samples of the same peptide graded A or B. Ordered by grade, then price per mg. Partner status never changes the order.
Retatrutide
M-Peptides: grade EM-Peptides products we've tested
Best-graded first. Grades come from the share of each product's samples that passed purity and quantity checks. Buy links open M-Peptides' site.
- TirzepatideBGOOD
- Tests
- 14
- Passed
- 85.7%
- RetatrutideEBAD
- Tests
- 10
- Passed
- 50.0%
What the testing shows
Across 24 measured samples from M-Peptides, 4 came in more than 5% under the quantity on the label (17%). Another 8 measured more than 5% over. Purity across 24 readings ran from 91.9% to 99.95%, median 99.82%. Samples span Jun 2025 to Sep 2026.
- Under label
- 4/24
- Median purity
- 99.82%
- Latest sample
- Sep 2026
more than 5% short
91.9%–99.95% range
first tested Jun 2025
Our read on M-Peptides
17 of M-Peptides' 24 graded samples passed (71%), and 100% of all samples were sent in by buyers rather than by the shop.
Results are improving: 83% passed over the latest six months, up from 67% before.
When a sample failed, the most common reason was purity under 99.5% (6 times).
Against the 302 shops with at least five graded tests, M-Peptides' pass rate is at or above 46% of them, and it has more tests on record than 57% of them.
When and how M-Peptides was tested
Samples per month. The darker part of each bar failed.
- Labs used
- Krause Analytical (18), BTLabs (5), Harrens Lab (1)
- Who sent the samples
- buyers 100%
- Batches covered
- 19 distinct batch numbers; 1 checked for endotoxins
Why M-Peptides' failed samples failed
The 6 most recent failed tests, with the lab's reason.
Retatrutide · Jun 22, 2026
purity under 99.5%
Retatrutide · Feb 18, 2026
amount in the vial more than 35% off the label
Retatrutide · Jan 7, 2026
purity under 99.5%
Tirzepatide · Nov 25, 2025
purity under 99.5%
Retatrutide · Oct 23, 2025
purity under 99.5%
Retatrutide · Oct 23, 2025
purity under 99.5%
Lab testing results
Independent results across 2 products.
Individual lab tests
Date
9/30/2026
Purity
99.9%
Quantity
50 mg → 49.99 mg
Lab
Harrens Lab
Vial
White label / Green crimp / Clear cap
Date
9/14/2026
Purity
99.9%
Quantity
30 mg → 32.6 mg
Lab
Krause Analytical
Vial
No label / Silver crimp / Pink cap
Date
6/22/2026
Purity
99.9%
Quantity
15 mg → 15.3 mg
Lab
Krause Analytical
Vial
No label / Silver crimp / Red cap
Date
6/22/2026
Purity
91.9%
Quantity
20 mg → 20.7 mg
Lab
Krause Analytical
Vial
White Label / Silver Crimp / Blue Cap
Date
6/12/2026
Purity
99.9%
Quantity
60 mg → 56.1 mg
Lab
Krause Analytical
Vial
No label / Silver crimp / Yellow cap
| Product | Date | Score | Purity | Quantity | Lab | COA |
|---|---|---|---|---|---|---|
| RetatrutideWhite label / Green crimp / Clear cap | 9/30/2026 | 10.0 | 99.9% | 50 mg → 49.99 mg | Harrens Lab | View |
| TirzepatideNo label / Silver crimp / Pink cap | 9/14/2026 | 10.0 | 99.9% | 30 mg → 32.6 mg | Krause Analytical | View |
| TirzepatideNo label / Silver crimp / Red cap | 6/22/2026 | 10.0 | 99.9% | 15 mg → 15.3 mg | Krause Analytical | View |
| RetatrutideWhite Label / Silver Crimp / Blue Cap | 6/22/2026 | 9.2 | 91.9% | 20 mg → 20.7 mg | Krause Analytical | View |
| TirzepatideNo label / Silver crimp / Yellow cap | 6/12/2026 | 10.0 | 99.9% | 60 mg → 56.1 mg | Krause Analytical | View |
Which M-Peptides products tested best
Tirzepatide has the strongest record, graded A or B.
Retatrutide graded D or E: a large share of its samples missed purity or quantity thresholds.
Buying from M-Peptides
If you order from M-Peptides, the A- and B-graded products are the safer picks on this record. For the weaker ones, the better-tested options on this page come from other shops.
We don't track M-Peptides' prices yet. Shipping, payment and refund terms are on their site.
The official store is discord.gg/qH8GJfRqXk https://t.me/MPeptidesScience https://mpeptidesscience.com. Check the address before you pay.
What to check before you pay
- The lot number on the vial matches the certificate
- The certificate names the lab and the test date
- Fill versus label, not purity alone
- A refund policy in writing
Track M-Peptides
Create a free account to save this vendor, get alerts for new lab tests, and watch price changes.
M-Peptides: common questions
Is M-Peptides legit?
We rate lab records, not businesses. Mixed lab record: 24 independent tests, 20 of 24 lots filled to label, median purity 99.82%, 1 of 2 products graded D or E. Each result links to its original certificate in the table above.
What do M-Peptides reviews say?
We don't hold scored customer reviews for M-Peptides yet. The independent lab results on this page are the evidence we have.
Which M-Peptides peptides tested best?
We have graded 2 M-Peptides products. Tirzepatide graded A or B. Retatrutide graded D or E.
Is there a M-Peptides coupon code?
We don't have a verified M-Peptides coupon code. A discount changes the price, not what is in the vial.
Ordering from M-Peptides?
Mixed lab record: 24 independent tests, 20 of 24 lots filled to label, median purity 99.82%, 1 of 2 products graded D or E.
About M-Peptides
Discord Vendor elsa@mps-m.com