ZLZ Peptide Review
ZLZ Peptide reviews: 309 independent lab tests across 14 products, with a mixed lab record.
Written by the Peptide Vendor Reviews editorial team
Is ZLZ Peptide legit? Lab record: Mixed
How we rate- 309 independent tests
- 237 of 302 lots filled to label
- Median purity 99.81%
- 4 of 13 products graded D or E
Some of ZLZ Peptide's products graded D or E. The shops below tested A or B for the same peptides.
Better-tested BPC-157
ZLZ Peptide graded E. Zenith Jove Peptide ZJ's BPC-157 graded A across 10 tests.
Buy from Zenith Jove Peptide ZJAll better-tested optionsPeptide Vendor Reviews independently tests products and verifies reviews. Public methodology, no pay-to-rank.
Better-tested options
Where ZLZ Peptide 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.
ZLZ Peptide 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 ZLZ Peptide's site.
- RetatrutideAGREAT
- Tests
- 114
- Passed
- 91.2%
- PT-141AGREAT
- Tests
- 3
- Passed
- 100.0%
- CagrilintideAGREAT
- Tests
- 3
- Passed
- 100.0%
- Melanotan IIAGREAT
- Tests
- 2
- Passed
- 100.0%
- TirzepatideBGOOD
- Tests
- 97
- Passed
- 85.6%
- GHK-CuBGOOD
- Tests
- 19
- Passed
- 84.2%
- IpamorelinBGOOD
- Tests
- 6
- Passed
- 83.3%
- CJC-1295BGOOD
- Tests
- 5
- Passed
- 80.0%
- SermorelinBGOOD
- Tests
- 5
- Passed
- 80.0%
- SemaglutideDPOOR
- Tests
- 13
- Passed
- 69.2%
- TesamorelinEBAD
- Tests
- 18
- Passed
- 38.9%
- BPC-157EBAD
- Tests
- 13
- Passed
- 46.2%
- TB-500EBAD
- Tests
- 6
- Passed
- 33.3%
- NAD+—
- Tests
- 5
- Passed
- —
What the testing shows
Across 302 measured samples from ZLZ Peptide, 65 came in more than 5% under the quantity on the label (22%). Another 118 measured more than 5% over. Purity across 306 readings ran from 40.4% to 100%, median 99.81%. Samples span Jun 2025 to Oct 2026.
- Under label
- 65/302
- Median purity
- 99.81%
- Latest sample
- Oct 2026
- Ships from
- China
more than 5% short
40.4%–100% range
first tested Jun 2025
per vendor listing
Our read on ZLZ Peptide
247 of ZLZ Peptide's 308 graded samples passed (80%), and 100% of all samples were sent in by buyers rather than by the shop.
The pass rate has held steady: 77% over the latest six months against 81% before.
When a sample failed, the most common reason was purity under 99.5% (49 times).
2 samples failed identity, meaning the lab could not confirm the vial held the labelled peptide.
Against the 302 shops with at least five graded tests, ZLZ Peptide's pass rate is at or above 71% of them, and it has more tests on record than 99% of them.
When and how ZLZ Peptide was tested
Samples per month. The darker part of each bar failed.
- Labs used
- Krause Analytical (202), BTLabs (94), Chromate (7), Harrens Lab (2)
- Who sent the samples
- buyers 100%
- Batches covered
- 98 distinct batch numbers; 20 checked for endotoxins
Why ZLZ Peptide's failed samples failed
The 6 most recent failed tests, with the lab's reason.
Retatrutide · Oct 12, 2026
purity under 99.5%
NAD+ · Oct 6, 2026
amount in the vial more than 35% off the label
Semaglutide · Oct 1, 2026
purity under 99.5%
Tirzepatide · Sep 24, 2026
purity under 99.5%; amount in the vial more than 35% off the label
NAD+ · Sep 24, 2026
purity under 99.5%
Tesamorelin · Jul 23, 2026
purity under 99.5%
Lab testing results
Independent results across 14 products.
Individual lab tests
Date
10/12/2026
Purity
99.9%
Quantity
120 mg → 137 mg
Lab
Krause Analytical
Vial
Silver crimp / White cap
Date
10/12/2026
Purity
98.9%
Quantity
20 mg → 18.2 mg
Lab
Krause Analytical
Vial
No label / Silver crimp / Pink cap
Date
10/8/2026
Purity
99.9%
Quantity
20 mg → 20.6 mg
Lab
Krause Analytical
Vial
No label / Copper crimp / Clear cap
Date
10/6/2026
Purity
99.9%
Quantity
500 mg → 1567.2 mg
Lab
BTLabs
Vial
No label / Copper crimp / Black cap
Date
10/6/2026
Purity
99.9%
Quantity
20 mg → 21.1 mg
Lab
BTLabs
Vial
No label / Silver crimp / Pink cap
| Product | Date | Score | Purity | Quantity | Lab | COA |
|---|---|---|---|---|---|---|
| TirzepatideSilver crimp / White cap | 10/12/2026 | 10.0 | 99.9% | 120 mg → 137 mg | Krause Analytical | View |
| RetatrutideNo label / Silver crimp / Pink cap | 10/12/2026 | 9.9 | 98.9% | 20 mg → 18.2 mg | Krause Analytical | View |
| RetatrutideNo label / Copper crimp / Clear cap | 10/8/2026 | 10.0 | 99.9% | 20 mg → 20.6 mg | Krause Analytical | View |
| NAD+No label / Copper crimp / Black cap | 10/6/2026 | 10.0 | 99.9% | 500 mg → 1567.2 mg | BTLabs | View |
| RetatrutideNo label / Silver crimp / Pink cap | 10/6/2026 | 10.0 | 99.9% | 20 mg → 21.1 mg | BTLabs | View |
Which ZLZ Peptide products tested best
PT-141, Melanotan II, Cagrilintide, Retatrutide, Tirzepatide, GHK-Cu, Ipamorelin, CJC-1295 and Sermorelin have the strongest record, graded A or B.
Semaglutide, BPC-157, Tesamorelin and TB-500 graded D or E: a large share of their samples missed purity or quantity thresholds.
Buying from ZLZ Peptide
If you order from ZLZ Peptide, 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 ZLZ Peptide's prices yet. Shipping, payment and refund terms are on their site.
The official store is www.zlzpeptide.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 ZLZ Peptide
Create a free account to save this vendor, get alerts for new lab tests, and watch price changes.
ZLZ Peptide: common questions
Is ZLZ Peptide legit?
We rate lab records, not businesses. Mixed lab record: 309 independent tests, 237 of 302 lots filled to label, median purity 99.81%, 4 of 13 products graded D or E. Each result links to its original certificate in the table above.
What do ZLZ Peptide reviews say?
We don't hold scored customer reviews for ZLZ Peptide yet. The independent lab results on this page are the evidence we have.
Which ZLZ Peptide peptides tested best?
We have graded 13 ZLZ Peptide products. PT-141, Melanotan II, Cagrilintide, Retatrutide, Tirzepatide, GHK-Cu, Ipamorelin, CJC-1295 and Sermorelin graded A or B. Semaglutide, BPC-157, Tesamorelin and TB-500 graded D or E.
Is there a ZLZ Peptide coupon code?
We don't have a verified ZLZ Peptide coupon code. A discount changes the price, not what is in the vial.
Where does ZLZ Peptide ship from?
Public listings place ZLZ Peptide's shipping origin in China. Check the shop's own shipping page before ordering, as origin can change.
Ordering from ZLZ Peptide?
Mixed lab record: 309 independent tests, 237 of 302 lots filled to label, median purity 99.81%, 4 of 13 products graded D or E.
Contact
- China
- www.zlzpeptide.com