Skincare expiry calculator

Yes, skincare expires, and the small open-jar symbol tells you when. A number such as 12M means the product is meant to be used within 12 months of opening it. Enter the date you opened it and the calculator gives you the date to use it by. If a printed expiry date comes sooner, that date wins.

Expired skincare is rarely dangerous in the dramatic way the internet sometimes suggests. The more common problem is quieter: an active that has broken down, a preservative that no longer keeps up, a sunscreen that no longer delivers the number on the front.

What does 12M mean on skincare?

It is the period-after-opening symbol, a drawing of an open jar with a number of months beside it. Under the EU cosmetics regulation, products that stay stable for more than 30 months unopened carry this symbol instead of a date, and products with a shorter shelf life must carry a date. Many products sold in the US carry the symbol too, although US law does not require cosmetics to show an expiry date at all.

How long does sunscreen last after opening?

Sunscreen is different, because in the US it is regulated as an over-the-counter drug. The FDA requires sunscreens to keep their original strength for at least three years. If a bottle has no printed expiry date, the FDA advises treating it as expired three years after you bought it. Heat shortens that: a bottle that has spent a summer in a hot car, or has changed colour or texture, should go sooner.

How long does vitamin C serum last?

Often less time than the symbol suggests, because L-ascorbic acid oxidises once air gets into the bottle. The colour is a better guide than the calendar. A serum that has turned from pale to dark yellow or brown has lost much of what you paid for, which I went into in the vitamin C entry. Keep the cap closed and the bottle out of light.

How long does mascara last?

Eye products have the shortest lives of anything in a makeup bag. According to the FDA, manufacturers usually advise replacing mascara two to four months after you start using it, because every pass of the wand carries bacteria back into the tube. If it dries out before then, replace it rather than adding water or saliva, which only brings in more bacteria.

Typical periods after opening

If a product has no symbol, or you can no longer read it, the calculator falls back on these typical figures. They are general guides, and the symbol on your own product is always more reliable.

Does expired skincare still work?

Partly, and unpredictably, which is the problem. Actives such as vitamin C and retinol lose strength, emulsions can separate, and preservatives weaken, which matters most in jars you dip your fingers into. A change in smell, colour or texture is a reason to stop regardless of the date. "It still looks fine" is not a reason to keep going past it, especially with sunscreen, where you cannot see a loss of protection at all.

For sunscreen in particular, the amount you use matters even more than its age, and the sunscreen calculator works that out for your face, body or a week away. Labels are also less reliable guides than they look, which is the same lesson as why natural is not a safety category.

Frequently asked

What does 12M mean on skincare?

It is the period-after-opening symbol: a small open jar with 12M beside it means the product is meant to be used within 12 months of opening. It is required in the EU for products that stay stable for more than 30 months unopened. The calculator adds that period to the date you opened it.

Does skincare expire if unopened?

Yes, but more slowly. An unopened product is protected from air and bacteria, so its printed date or its shelf life applies rather than the open-jar symbol. In the EU, products that last 30 months or less must carry a date. Heat and sunlight shorten shelf life whether or not the product has been opened.

How long does sunscreen last after opening?

Check the date or symbol on the bottle first. In the US, sunscreens must keep their full strength for at least three years, and one with no printed expiry date should be treated as expired three years after purchase. A bottle that has changed colour or texture, or baked in a hot car, should go sooner.

How long does mascara last?

According to the FDA, manufacturers usually advise replacing mascara two to four months after you start using it, because the wand carries bacteria back into the tube every time. If it dries out before then, replace it rather than adding water or saliva, which only brings in more bacteria.