Olaplex Numbers Explained: What Olaplex No 3 and the Rest Are For

How the Olaplex no 3 and number finder works

Pick a use, such as a pre-wash step, a curl routine, toning blonde hair or a weekly mask, and the finder shows the products the brand describes for it. Each one comes with the brand’s directions, how often to use it, and a link to the page those directions came from. There are entries for No.1, No.2 and No.8 too, because those are the numbers people ask about most and can’t find on the shelf.

The finder doesn’t rank or recommend products, and it doesn’t repeat marketing claims. It answers one question: which number is for what. If you want the products in order for your own hair, the routine builder does that next.

What Olaplex No 3 is for

No.3 was the brand’s best-known product for years. Today the old No.3 page opens the No.3PLUS page, and the brand’s FAQ describes No.3PLUS as the next version of it. Its directions are short: in the shower, apply generously to wet hair from roots to ends, leave it on for 3 minutes, rinse, then follow with shampoo and conditioner. The page says it can be used every 1 to 3 washes or even daily, and its FAQ adds that once or twice a week is enough and that there’s no need to leave it on overnight.

The most common mix-up is when to use it. It goes before shampoo, not after, so the shampoo and conditioner come last. If you have an older bottle of No.3, follow the directions printed on that label, since they may differ.

A few practical points help it fit into a real week. Because it goes on wet hair and only needs 3 minutes, it’s easiest to apply first thing in the shower and let it sit while you wash your body, then rinse and move on to shampoo. You don’t need to use it every wash: if you wash most days, every second or third wash fits the brand’s range. And because it’s rinsed out before shampoo, it doesn’t replace your conditioner, which still goes on afterward. If you’re not sure where it belongs alongside the rest of your products, the routine builder puts it in order for your hair type and goal.

No.0, No.1 and No.2

No.0 is an occasional extra step paired with No.3PLUS. The brand’s order is No.0 on dry hair for 10 minutes without rinsing, then No.3PLUS combed through on top for another 10 minutes, then rinse, shampoo and condition. It isn’t part of an everyday routine. No.1 and No.2 aren’t sold on the brand’s US shop. Its FAQ says they’re used in salons during chemical services such as bleach and color, and that they’re a different system from No.3PLUS, so ask your colorist about them rather than looking for them at home.

No.4 and No.5: shampoo and conditioner

Four is always a shampoo and five is always its conditioner, and the letters tell you the version. No.4 and No.5 are the everyday pair. No.4Fine and No.5Fine are the volumizing pair for fine hair. No.4CURL and No.5CURL are the curl pair. No.4P and No.5P are the purple toning pair for blonde, lightened or gray hair, and the brand’s toning labels ask for a patch test before first use. No.4C is a clarifying shampoo for weekly use, or as needed, in place of your regular shampoo. No.4D is different again: it’s a dry shampoo for roots between washes.

The conditioners go on mid-lengths and ends after the matching shampoo, for 1 to 3 minutes, then rinse. The brand bases its bottle counts on about 2.5 mL of shampoo and 5 mL of conditioner per use, so a little goes further than you might think.

No.6, No.7, No.9 and No.10: after you wash

These are the leave-on numbers. No.6 is a styling cream: one pump on freshly washed, damp hair, combed through before styling. No.7 is an oil: two or three drops on damp or dry hair, before heat styling or after it, and the brand says it can be used daily. No.9 is a serum for damp hair, worked from the ends up to the roots before you air-dry, blow-dry or diffuse. No.10 is a curl gel for wet hair, applied in sections and scrunched upward, with the cast scrunched out once it’s dry.

What happened to No.8?

No.8 was the brand’s numbered hair mask, and it’s one of the numbers people search for most. On October 11, 2026, it isn’t among the products listed on the brand’s US website. The weekly masks it lists now are the Rich Hydration Mask, for dry or medium to thick hair, and the Weightless Nourishing Mask, for fine hair. Both go on after shampoo, on wet mid-lengths and ends, for 3 to 5 minutes, once a week in place of conditioner. If you still have a jar of No.8, follow the directions on its label.

Every Olaplex number at a glance

The masks and the leave-in conditioner don’t have numbers, but they’re in the table because they sit alongside the numbered products in most routines. The brand also sells styling sprays and sets; this page sticks to the core line.

Before a wedding or event

If you’re planning hair for a wedding, try any new product at least four weeks before, not the week of. Tell your stylist what you use, especially oils, serums and creams, because they can change how well hair holds pins and curls, and your stylist may ask you to skip them on the day.