Guide
What is a cosmetic LOT number?
A short guide to batch codes and why they matter.
01 What is a LOT (batch) code?
A LOT or batch code is a short string printed or embossed on cosmetic packaging. It identifies the production batch — when and where the product was made. Unlike an expiry date, it isn't human-readable on its own; each brand encodes the date differently.
02 Why does it matter?
Cosmetics have a limited shelf life. Knowing the manufacturing date lets you estimate freshness and the period-after-opening, verify authenticity, and avoid selling or using expired products during inspection.
03 Where do I find it?
Look for a small printed or stamped code on the bottom of the bottle, the crimp of a tube, or the box flap. It usually mixes letters and numbers, e.g. "B1R1" or "3A21". This is different from the larger barcode.
04 How this tool reads it
Each brand belongs to a decoding group with its own rules. Pick the brand, enter the code, and we apply that brand's rule to recover the manufacturing date — then add three years for an estimated expiry.