Pillar I · Secret Key Batch Code Checker
Secret Key Batch Code Checker — lot number & freshness guide
Lot Stamp (Date Not Encoded) · [Lot number, 3–12 letters or digits][Production date not publicly encoded] · checked privately in your browser.
Lot Stamp (Date Not Encoded) · Houses without a published date code
[Lot number, 3–12 letters or digits][Production date not publicly encoded] · e.g. L24105
Where Secret Key stamps its code: outer box base crimp + flacon base
Ink-jet printed on the underside of Starting Treatment Essence glass bottles and embossed on tube crimps
- Read the code off the box base crimp in raking light — authentic embossing has uniform depth.
- Read the flacon base or label code and enter it above — the two must match character for character.
- Check for scraped, re-embossed or stickered-over crimps: a classic way to hide aged gray-market stock.
Printable guideWhere to Find Your Code (Tap to Zoom) ↓ Download WebP
Parent Conglomerate Pattern · Houses without a published date code
How Secret Key Codes Are Structured
- Pattern
- Lot Stamp (Date Not Encoded)
- Group
- Houses without a published date code
- Structure
- [Lot number, 3–12 letters or digits][Production date not publicly encoded]
- Length
- 3 or 4 or 5 or 6 or 7 or 8 or 9 or 10 or 11 or 12 characters
- Stamped On
- outer box base crimp · flacon base
- Confidence
- Reference only — the code identifies the production lot, but no production date can be read from it. Use the printed EXP / MFD date or the PAO symbol, or ask the brand to date the lot number.
- Reported Notes
- Zenpia Co., Ltd. / Secret Key Korea (Starting Treatment Essence Rose Edition, Lemon Sparkling Peeling Gel & Black Out Pore Clean Remover) prints Korean YYYY.MM.DD manufacture/expiration dates paired with a 4-to-6 character lot code on bottle bases. (reported, not verified by Beauty.net)
- Where to Look
- Ink-jet printed on the underside of Starting Treatment Essence glass bottles and embossed on tube crimps
Worked Decode · L24105 → Not date-encoded
| Sample Code | Production Date | Verdict (as of November 2026) |
|---|---|---|
| L24105 | Not date-encoded | Lot Recorded — Check the Printed Date |
| 3145A | Not date-encoded | Lot Recorded — Check the Printed Date |
| B2209A | Not date-encoded | Lot Recorded — Check the Printed Date |
Secret Key has not published how its lot code encodes the production date, so no date is estimated. Read the printed EXP / MFD date or the PAO (open-jar) symbol, or give the lot number to the brand's customer service.
Beauty.net does not estimate dates for houses without a published code structure. Reported notes: batch-code reference, not verified by Beauty.net. A valid format never proves authenticity.
Searchable in the Decoder
Popular Secret Key Products
- secret key
- secret key starting treatment essence
- secret key rose edition
- secret key lemon sparkling peeling gel
- secret key snow white cream
Section V · Formulation Audit
Audited Formulations From Secret Key
-
Starting Treatment Essence Rose Edition (94% Galactomyces Ferment Filtrate + Rosa Centifolia Flower Water + Niacinamide + Adenosine — Fragrance-Free) →
Brightening · 94% Galactomyces Ferment Filtrate, Rosa Centifolia Hydrosol, Niacinamide & Adenosine First Treatment Essence
Skincare is best used within about 36 months of production and 6–12 months of opening.
Field Notes
Frequently Asked Questions
Can I decode a Secret Key batch code?
Secret Key has not published how its lot code encodes the production date, so Beauty.net records the lot number and checks its format but does not estimate a date. Reported notes (from the batch-code reference cited below, not verified by Beauty.net): Zenpia Co., Ltd. / Secret Key Korea (Starting Treatment Essence Rose Edition, Lemon Sparkling Peeling Gel & Black Out Pore Clean Remover) prints Korean YYYY.MM.DD manufacture/expiration dates paired with a 4-to-6 character lot code on bottle bases. To check freshness, read the printed EXP or MFD date or the PAO (open-jar) symbol, or give the lot number to Secret Key customer service. A correctly formatted code never proves authenticity.
Where is the batch code stamped on a Secret Key box and bottle?
Ink-jet printed on the underside of Starting Treatment Essence glass bottles and embossed on tube crimps Look on the outer box base crimp and the flacon base. The code on the box and the code on the flacon must match character for character; a scraped, re-embossed or stickered-over box crimp is a classic sign of aged gray-market stock.
How long does Secret Key last and where can I buy fresh-batch authentic products in Singapore?
Unopened, Secret Key skincare is a fresh batch for 24 months from production and should be used within about 36 months, as vitamin C, retinoids and peptides degrade with time. In Singapore, buy from Secret Key authorised counters and the brand's official online store, and check that the printed EXP / MFD date is recent before you pay.