You open a new Korean serum, glance at the box, and find a string of letters and numbers, a small open-jar symbol, and a line of Korean text you cannot read. Which one is the expiry date? Is the batch code the same thing? This guide explains what each marking means, where to find it, and how to use it before you buy or open a product.
Quick answer: Check three separate things: a batch or lot code (usually on the base, tube crimp, or box), a printed expiry or use-by date (often labeled 사용기한 or ending in 까지), and a PAO symbol such as 12M showing how long the product stays usable after opening. Use the printed expiry first, then the PAO. A batch code alone never proves authenticity.
Who this guide is for
This is for anyone buying or storing Korean skincare in Bangladesh who wants to judge age and freshness before using a product. It is a practical reading guide, not a guarantee that a product is safe or genuine. If a product causes persistent irritation, stop using it and speak to a qualified clinician, whatever its dates say.
The three markings, and why they are different
| Marking | What it tells you | Where to look |
|---|---|---|
| Batch or lot code | An internal manufacturing reference, usually a short mix of letters and numbers. On its own it does not state an expiry date. | Base of the bottle or jar, tube crimp, bottom or flap of the box |
| Expiry or use-by date | The date until which the unopened product is intended to remain usable | Same areas, sometimes beside Korean or English wording |
| PAO symbol | An open-jar icon with a number such as 6M, 12M, or 18M: the recommended months of use after you first open the product | Back of the container or the box |
The PAO is a guideline for time in use, so it does not replace the expiry date. A sealed product can be within its expiry and still be old, and an opened product can pass its PAO before the printed expiry date arrives.
How to read Korean date labels
Korean packaging often prints dates with Korean wording beside them. Read the label next to the date before deciding what the date means:
- 제조 or 제조일: manufacture, meaning the date the product was made.
- 사용기한: the use-by or expiry limit.
- 까지: "until", so a date followed by 까지 usually marks the end of the usable period, not the day it was made.
- 제조번호: the manufacturing or lot number, which is the batch code.
Dates are commonly printed in a year.month.day style, so a line like 2027.06.15 followed by 까지 would point to a mid-June 2027 limit. The same date without that wording could mean manufacture. When in doubt, keep the Korean label and the date in the same photo so the meaning stays clear, and compare it with the brand's official product pages.
Where to look on different packaging
- Bottles and jars: underneath, or on the lower back label.
- Tubes: along the sealed crimp at the end.
- Cartons: the bottom, side, or flap, which sometimes carries a different print from the container.
- Sachets and sheet masks: along the sealed edge of the pouch.
Look for the code and date on both the container and the carton, because they should be consistent. Printed codes can fade with handling, particularly on oily or wet surfaces, so photograph them when you receive the product.
What a batch code can and cannot tell you
Online batch code lookups estimate when a product was manufactured, which is useful context for judging age. They do not confirm that a product is genuine, because a counterfeiter can print a real batch code on a fake product. Use the code as one data point alongside the seller, packaging quality, and price. Keep barcodes, SKUs, volume, SPF values, and ingredient percentages out of the picture too, since none of these is a batch code.
How shelf life works in practice
Under European rules, products that last longer than 30 months unopened need a PAO symbol, while products with a shorter life carry a "best used before" date instead. Korean-market packaging may follow Korean labeling conventions, so you will not always see both markings on every product, and the exact requirements for products sold in Bangladesh depend on local rules. Whichever markings are present, the practical approach is the same: use a clearly printed expiry date first, then the PAO once the product is opened.
As a rough guide, creams, serums, and sunscreens commonly carry a PAO of around 12 months, though the pack's own symbol overrides any general figure. Written down on the container, the date you first opened a product makes this easy to track.
Bangladesh climate context
Heat and humidity speed up the wear on skincare in ways a printed date cannot capture. Storage temperature matters, so products kept on a sunny shelf, near a window, or in a hot courier van can degrade before their dates arrive. Sunscreens, vitamin C, and retinoids are particularly sensitive, and an expired sunscreen may no longer give the protection stated on its label, which matters in a country with strong sun all year.
Practical habits help: store products in a cool, dry cupboard away from direct light, close lids after each use, and avoid leaving them in bags or vehicles. Check the date when buying as well as when opening, because a longer remaining shelf life gives you a better margin in hot, humid conditions.
A simple check before you buy or open
- Find the batch code, the expiry or manufacture date, and any PAO symbol on both the container and the carton.
- Read the Korean wording beside the date (제조 for manufacture, 사용기한 or 까지 for the use-by limit).
- Confirm the remaining shelf life is comfortable for how quickly you will use the product.
- Photograph the codes and dates when the product arrives, before you open it.
- Write the opening date on the container, and discard the product once the PAO has passed.
- Check the product for changes in smell, color, separation, or texture before every use.
Mistakes and cautions
- Treating a batch code as an expiry date. The code identifies production, and dates need to be read from the date line itself.
- Assuming any date on the box is the expiry. A date beside 제조 means manufacture, while 사용기한 or 까지 marks the limit.
- Ignoring the PAO after opening. A product can be within its printed expiry but past its recommended time in use.
- Using sunscreen past its date. An expired SPF may no longer protect as labeled, so replace it.
- Keeping products in heat. Warm storage can degrade a product before its date, so cooler is better.
- Relying on a batch checker for authenticity. It estimates production timing and does not prove a product is real.
Frequently asked questions
Where do I find the batch code on Korean skincare?
Check the base of the bottle or jar, the sealed crimp of a tube, and the bottom or flap of the carton. On Korean packs it may sit near the label 제조번호.
What does 까지 mean on a Korean skincare box?
It means "until". A date followed by 까지 usually marks the end of the period the product is intended to be used, not the date it was made.
What does the open-jar symbol with 12M mean?
It is the period after opening (PAO). 12M means the product is recommended for use for 12 months after you first open it. The number varies by product, so read the one on your pack.
Can I use skincare past its expiry date?
It is best not to. Using expired products can reduce effectiveness and may cause irritation or breakouts. Sunscreen is especially important to replace on time, because it may no longer protect as stated.
Does a valid batch code prove my product is genuine?
No. A batch code tells you roughly when a product was made, and fake products can carry real codes. Combine it with checks on the seller, packaging quality, and price.
What if my product has no expiry date or PAO?
Be cautious. Missing, smudged, or inconsistent dates are a warning sign. Ask the seller for clear photos of the codes before buying, and consider choosing another product if they cannot provide them.
Reading labels with confidence
Checking the batch code, expiry date, and PAO takes a minute and gives you a much clearer picture of what you are buying. Browse Skincare Mart and check each product page for current details before you order, and apply the same checks to anything you receive.
