Guide
How to Test Your Hair Porosity
Three at-home porosity tests, why the float test misleads, and what each result changes about what you buy.
Top pick: Curlsmith Weightless Air Dry Cream
Start here — which am I?
Hair Types & Porosity
Before you buy anything, settle two questions: how thick each strand is, and how readily it takes in water. Almost every product decision follows from those two.
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Start here
Curlsmith Weightless Air Dry Cream
The curl cream for people whose curls collapse under a normal curl cream. Curlsmith builds it on hyaluronic acid rather than heavy butters, so it hydrates without the weight.
Our top pick in The Best Products for Low Porosity Hair.
Everything in this section
Hair Types & Porosity, page by page
Best for Low Porosity
The Best Products for Low Porosity Hair
Five lightweight picks for hair that resists absorbing product, plus the heat and clarifying tricks that make them work.
Top pick: Curlsmith Weightless Air Dry Cream
Best for High Porosity
The Best Products for High Porosity Hair
Five rich products and a sealing step for hair that drinks moisture and loses it, plus the protein balance to watch.
Top pick: Briogeo Don't Despair, Repair! Deep Conditioning Mask
Best for Fine Hair
The Best Shampoo for Fine Hair
Five lightweight shampoos for fine hair, and the placement rule that matters as much as which you buy.
Top pick: Verb Ghost Shampoo
Best for Men
The Best Hair Products for Men
Five products for a short, realistic men's routine, and an honest note on gendered marketing.
Top pick: Every Man Jack 2-in-1 Shampoo + Conditioner, Tea Tree
Best Drugstore Shampoo
The Best Drugstore Shampoo
Six drugstore shampoos sorted by problem, plus an honest note on where paying more actually buys something.
Top pick: L'Oréal Paris EverPure Sulfate-Free Moisturizing Shampoo
Guide
A Hair Care Routine by Hair Type
Four routines built on strand thickness and porosity, the two variables that actually predict what works.
Top pick: Verb Ghost Shampoo
Guide
A Beginner Hair Care Routine
Four products, four steps, nothing optional — plus what to add later and what to ignore entirely.
Top pick: L'Oréal Paris EverPure Sulfate-Free Moisturizing Shampoo
Two questions decide almost everything
Most hair care goes wrong at the diagnosis rather than the purchase. Before any product choice makes sense, you need to know two things about your hair, and neither is the curl type everyone talks about.
How thick is a single strand? Pull one out and roll it between your fingers. If you can barely feel it, your hair is fine. If it feels like a piece of thread, it is coarse. This is not the same as how much hair you have — you can have a great deal of fine hair, or not much coarse hair. Strand thickness decides how much weight your hair can carry before it goes flat, which decides whether a rich cream is going to work or ruin your day.
How readily does it take in water? That is porosity, and it governs whether product sinks in or sits on top. Porosity is a physical property of the fiber, and it is measurable — researchers assess it directly as a way of studying hair damage (true porosity measurement of hair, PubMed). You can get a good practical read in a few minutes at home; the porosity test guide shows how, and why the popular float-a-strand-in-water version is unreliable.
What porosity means at the shelf
Low porosity hair has a tightly packed cuticle. Water beads on it, it takes ages to get properly wet and ages to dry, and product sits on the surface and feels greasy rather than absorbing. Low-porosity hair needs lightweight products, warmth to help them in, and clarifying more often than you would think, because buildup has nowhere to go. See products for low porosity hair.
High porosity hair has a raised or damaged cuticle. It soaks up water instantly, dries fast, drinks product and still feels dry an hour later, and frizzes the moment the air gets humid. It needs heavier products, protein, and a sealing step — see products for high porosity hair. High porosity is usually acquired rather than inherited: bleaching, in particular, raises it substantially (acid straightening and bleaching in hair microstructures, PMC).
Where curl type fits
The 1 through 4 typing system describes curl shape: straight, wavy, curly, coily. It is genuinely useful for predicting how your hair behaves when it dries and how quickly sebum travels down the strand — which is why coily hair tends to be dry at the ends and straight hair greasy at the roots.
What it does not tell you is how much weight your hair can take, and that is the thing that most often decides whether a product works. Two people with identical 3b curls and different strand thicknesses need different products. If you only remember one thing from this section, make it that one.
Building a routine from those answers
Once you know strand thickness and porosity, the routine largely writes itself: how often to wash, whether to use a cream or a mousse, whether you need protein, whether an oil will seal or suffocate. Hair care routine by hair type lays out four routines by those two axes, and the beginner routine is the four-product version if you are starting from nothing.
The AAD's general guidance is a good sanity check on any routine you build: shampoo the scalp rather than the lengths, condition the ends, detangle wet hair gently with a wide-tooth comb, and adjust wash frequency to your hair type rather than to a rule (AAD, everyday hair care).
Where to go from here
Once you know what you have, take the route that matches the problem: dry and damaged, frizz and curls, thinning and growth, oily roots or color-treated. If money is the constraint rather than diagnosis, the drugstore shortlist is where we would start.