Hair porosity quiz: work out how your hair actually behaves

Thick Roots editorial deskUpdated September 2026Method: observable behaviour, not the float test
Short answer

Six questions on how your hair behaves: how fast it wets, how long it takes to dry, how it holds leave-in product, how it feels a day after washing, and how much heat and chemical processing it has had. You get a porosity band with the routine that suits it, and an honest note on its limits.

Answer for how your hair behaves today, not for how it behaved before the last colour or the last year of straightening. Hair changes, and so should the answer.

How porous is your hair?

Six questions, about a minute. Answer for the hair you have now, on a normal week, not for a best hair day.

When your hair gets fully wet in the shower, what happens?

How long does your hair take to air dry?

What do leave-in products do on your hair?

What does your hair feel like the day after washing?

How much heat and chemical processing has your hair had in the last year?

Run one strand between your fingers from root to end. How does it feel?

How this quiz scores, and its limits

Method type: an editorial weighting, not a validated clinical instrument.
Not suitable for: diagnosis, treatment selection, or any decision about pain, injury or illness.
Accountable publisher: the editorial desk of this store. Method version: 1.0. Last checked: 2026-09-14.

6 questions, each answer carrying a weight of zero or more. The weights are added and the total selects one of 4 result bands. The calculation runs in your browser; this quiz's own code does not save or transmit your answers. Separate site analytics are described in our privacy policy.

Band Result
1 Low porosity, or a fairly intact cuticle
2 Medium porosity, or the middle of the range
3 Higher porosity, or a lifted cuticle in places
4 High porosity, or significant cuticle damage

What this result cannot tell you. The weightings are editorial judgements drawn from the sources listed on this page; no study validates the scoring, the thresholds or the order of the advice. The result reflects the answers you gave, not a measurement of your situation. It is not a diagnosis, a professional assessment, or a substitute for advice from a qualified person. If your situation involves pain, injury, illness or a safety decision, treat the result as a prompt to get that advice rather than as the advice itself.

What porosity means, and the honest limit

Porosity describes how easily water and small molecules move into and out of the hair fibre. A cuticle that is intact slows that movement down. A cuticle that has been lifted, chipped or worn away speeds it up. The direction of that relationship is well established in hair science.

The evidence is thinner than the internet suggestsPorosity is real as a property of hair, but the reference way to measure it is gas sorption in a laboratory, not a glass of water at home (Hessefort et al., 2008). The popular float test mostly measures surface tension and how damaged the surface is, so it can sort the same head of hair differently on different days. And the product rules that circulate for each porosity band come from hair-care practice, not from published head-to-head trials. Treat your result as a working hypothesis that saves you time, and let your own hair overrule it.
Band Feels like The one change that helps most
Low Slow to wet, slow to dry, product sits on top Less product, on damp hair, with warmth
Medium Behaves normally, holds product well Keep it simple and retest after any chemical service
Higher Dries fast, feels rough, drifts dry Reduce heat and detangle with slip
High Soaks up water and product, still dry Trim back, seal the ends, stop the heat

Three levers that matter more than your band

  1. Heat. A flat iron above 200C degrades the keratin and the cuticle, and increases breakage afterwards (Zhou et al., 2011). Lower temperature and fewer passes beats the alternative.
  2. How you detangle. Wet combing is a documented mechanical damage route, and coconut oil reduced protein loss from hair in the laboratory comparison that measured it (Rele and Mohile, 2003). Conditioner plus a wide comb, ends first.
  3. How often you wash. Ordinary washing is not the thing wrecking your hair. In a controlled comparison, daily washing outperformed weekly washing on flaking, itching and inflammatory markers, with no measured hair damage (Punyani et al., 2021).

Test one change properly

Your result points at a direction, not a prescription. Change one thing at a time or you will never know what worked:

  1. Pick one change from your band, and only one.
  2. Keep everything else in your routine identical for three washes.
  3. Take a photo in the same light, same place, same time of day, dry and unstyled.
  4. Compare at the end of the three washes. Keep it, drop it, or adjust it.

That is also how we test the claims on this site. The how we research and test page sets out the standard.

Use these next

One thing this quiz cannot tell youPorosity says nothing about whether you are losing hair, and no porosity band causes hair loss. Sudden shedding, smooth patches, a painful scalp or scaling with redness need a clinician rather than a different leave-in.

Sources

  1. Hessefort YZ, Holland BT, Cloud RW. True porosity measurement of hair: a new way to study hair damage mechanisms. J Cosmet Sci 2008;59(4):303-315 — pubmed.ncbi.nlm.nih.gov/18818850
  2. Zhou Y, Rigoletto R, Koelmel D, et al. The effect of various cosmetic pretreatments on protecting hair from thermal damage by hot flat ironing. J Cosmet Sci 2011;62(2):265-282 — pubmed.ncbi.nlm.nih.gov/21635854
  3. Rele AS, Mohile RB. Effect of mineral oil, sunflower oil, and coconut oil on prevention of hair damage. J Cosmet Sci 2003;54(2):175-192 — pubmed.ncbi.nlm.nih.gov/12715094/
  4. Punyani S, Tosti A, Hordinsky M, Yeomans D, Schwartz J. The impact of shampoo wash frequency on scalp and hair conditions. Skin Appendage Disord 2021;7(3):183-193 — pmc.ncbi.nlm.nih.gov/articles/PMC8138261/
  5. NHS. Hair loss: causes and treatment — www.nhs.uk/conditions/hair-loss

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