YuYi peptide reviews
YuYi peptide reviews: 9 independent lab tests across 2 products, with a limited lab record.
Written by the Peptide Vendor Reviews editorial team
Is YuYi peptide legit? Lab record: Limited
How we rate- 9 independent tests
- 6 of 6 lots filled to label
- Median purity 99.8%
- 1 of 2 products graded D or E
Some of YuYi peptide's products graded D or E. The shops below tested A or B for the same peptides.
Better-tested Tirzepatide
YuYi peptide graded D. Paradigm Peptide's Tirzepatide graded A across 10 tests, $4.97 / 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 YuYi 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.
YuYi 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 YuYi peptide's site.
- RetatrutideBGOOD
- Tests
- 5
- Passed
- 80.0%
- TirzepatideDPOOR
- Tests
- 4
- Passed
- 66.7%
What the testing shows
Across 6 measured samples from YuYi peptide, 0 came in more than 5% under the quantity on the label (0%). Purity across 7 readings ran from 99.3% to 99.9%, median 99.8%. Samples span Oct 2025 to Oct 2026.
- Under label
- 0/6
- Median purity
- 99.8%
- Latest sample
- Oct 2026
- Ships from
- China
more than 5% short
99.3%–99.9% range
first tested Oct 2025
per vendor listing
Our read on YuYi peptide
6 of YuYi peptide's 8 graded samples passed (75%), and 100% of all samples were sent in by buyers rather than by the shop.
Results are slipping: 67% passed over the latest six months, down from 80% before.
When a sample failed, the most common reason was no purity figure on the certificate (1 time).
1 sample failed identity, meaning the lab could not confirm the vial held the labelled peptide.
Against the 302 shops with at least five graded tests, YuYi peptide's pass rate is at or above 57% of them, and it has more tests on record than 27% of them.
When and how YuYi peptide was tested
Samples per month. The darker part of each bar failed.
- Labs used
- BTLabs (6), Krause Analytical (2), Harrens Lab (1)
- Who sent the samples
- buyers 100%
- Batches covered
- 3 distinct batch numbers; 1 checked for endotoxins
Why YuYi peptide's failed samples failed
The 2 most recent failed tests, with the lab's reason.
Tirzepatide · Jun 8, 2026
purity under 99.5%; amount in the vial more than 35% off the label
Retatrutide · Dec 29, 2025
the lab could not confirm it was the labelled peptide
Lab testing results
Independent results across 2 products.
Individual lab tests
Date
10/9/2026
Purity
99.9%
Quantity
30 mg → 29.99 mg
Lab
Harrens Lab
Vial
Silver crimp / White cap
Date
6/16/2026
Purity
99.7%
Quantity
5 mg → 5.1 mg
Lab
BTLabs
Vial
White label / Silver crimp / Yellow cap
Date
6/16/2026
Purity
—
Quantity
—
Lab
BTLabs
Vial
White label / Silver crimp / Blue cap
Date
6/8/2026
Purity
99.3%
Quantity
5 mg → 10 mg
Lab
BTLabs
Vial
Clear label / Silver crimp / Yellow cap
Date
1/22/2026
Purity
99.8%
Quantity
10 mg → 9.8 mg
Lab
BTLabs
Vial
White Label / Silver Crimp / Green Cap
| Product | Date | Score | Purity | Quantity | Lab | COA |
|---|---|---|---|---|---|---|
| RetatrutideSilver crimp / White cap | 10/9/2026 | 10.0 | 99.9% | 30 mg → 29.99 mg | Harrens Lab | View |
| RetatrutideWhite label / Silver crimp / Yellow cap | 6/16/2026 | 10.0 | 99.7% | 5 mg → 5.1 mg | BTLabs | View |
| TirzepatideWhite label / Silver crimp / Blue cap | 6/16/2026 | — | — | BTLabs | View | |
| TirzepatideClear label / Silver crimp / Yellow cap | 6/8/2026 | 9.9 | 99.3% | 5 mg → 10 mg | BTLabs | View |
| RetatrutideWhite Label / Silver Crimp / Green Cap | 1/22/2026 | 10.0 | 99.8% | 10 mg → 9.8 mg | BTLabs | View |
Which YuYi peptide products tested best
Retatrutide has the strongest record, graded A or B.
Tirzepatide graded D or E: a large share of its samples missed purity or quantity thresholds.
Buying from YuYi peptide
If you order from YuYi 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 YuYi peptide's prices yet. Shipping, payment and refund terms are on their site.
The official store is hunmer.github.io/yuyi-peptide. 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 YuYi peptide
Create a free account to save this vendor, get alerts for new lab tests, and watch price changes.
YuYi peptide: common questions
Is YuYi peptide legit?
We rate lab records, not businesses. Limited lab record: 9 independent tests, 6 of 6 lots filled to label, median purity 99.8%, 1 of 2 products graded D or E. Each result links to its original certificate in the table above.
What do YuYi peptide reviews say?
We don't hold scored customer reviews for YuYi peptide yet. The independent lab results on this page are the evidence we have.
Which YuYi peptide peptides tested best?
We have graded 2 YuYi peptide products. Retatrutide graded A or B. Tirzepatide graded D or E.
Is there a YuYi peptide coupon code?
We don't have a verified YuYi peptide coupon code. A discount changes the price, not what is in the vial.
Where does YuYi peptide ship from?
Public listings place YuYi peptide's shipping origin in China. Check the shop's own shipping page before ordering, as origin can change.
Ordering from YuYi peptide?
Limited lab record: 9 independent tests, 6 of 6 lots filled to label, median purity 99.8%, 1 of 2 products graded D or E.