Type 4 hair is coily — coils 3 to 6 millimetres wide, the diameter of a coffee stirrer, with shrinkage that hides up to 75% of the hair's true length. Within type 4 sit three distinct sub-patterns: 4A coils, 4B Z-pattern bends, 4C tightly packed coils that read as cottony from a distance. The product logic for each is different. This is the type 4 care foundation: how to tell 4A from 4B from 4C, the wash-day routine each needs, and why type 4 needs more moisture than any other curl pattern.
Type 4 Hair: What Makes It Different from Types 2 and 3
The shorthand answer — that type 4 coils tighter than type 3 — undersells the actual biology. Type 4 hair grows from follicles that are flattened in cross-section rather than round (type 1) or oval (types 2 and 3). That flattening is what produces the tight coiling. It also produces a strand that has more bends per centimetre than any other curl pattern, and every bend is a structural weak point where the cuticle layer naturally lifts away from the cortex.
Audrey Davis-Sivasothy's The Science of Black Hair (Saja Publishing, 2011) calls this "cuticle scalloping" — the cuticle scales on coiled hair are smaller, less densely packed, and sit at a steeper angle to the cortex than on straight or wavy hair. The practical consequence is that type 4 hair is structurally more permeable to water (and product) and structurally less able to hold onto either once let go. That's where the moisture-first model for type 4 comes from. It isn't a stylist preference. It's geometry.
The other measurement that separates type 4 from types 2 and 3 is shrinkage. We covered the chart in detail in the complete curl type chart, but as a refresher: 2A waves shrink under 15% when dry, 3B curls shrink 35–50%, and type 4 shrinks anywhere from 50% to 75% depending on sub-pattern. That last range — the 50-to-75% spread inside type 4 alone — is what makes lumping 4A, 4B and 4C together a mistake. They are not the same hair. The product logic isn't the same either.
4A Hair: Coily with Visible Spiral
4A is the loosest of the type 4 patterns — coils 4 to 6 millimetres wide with a visible springy spiral. The diameter sits between a coffee stirrer (4 mm) and a thin drinking straw (6 mm). The pattern resembles type 3C in shape but the strand circumference is type 4 — the coil holds its shape more rigidly and the strand bends more often per centimetre than a 3C strand would.
Shrinkage for 4A runs 50–65% when air-dried with no manipulation. The S-spiral is visible to the naked eye, and 4A is the type 4 sub-pattern most often featured in stock photography for "natural hair," which is part of why so much general "type 4" advice doesn't generalise to 4B or 4C wearers — the visual reference point in the writer's head is 4A and they don't realise it.
Density on 4A typically runs 250–300 hairs per cm² (high), and porosity skews medium-high. The 4A wash-day pattern that works for most: cleansing shampoo every 7–10 days, co-wash on the in-between wash days, deep-condition once a week, leave-in plus a thick cream or butter on every wash day, sealed with a light oil. Refresh between washes every two days with a water-and-leave-in spray. Thick creams (Oyin Handmade Whipped Pudding, SheaMoisture Curl Enhancing Smoothie) sit well on 4A without weighing the spiral down — at this coil diameter, the curl is structurally strong enough to hold its shape under product weight that would flatten a 3B.
4B Hair: The Z-Pattern Pattern
4B doesn't form round coils at all. It bends in sharp Z-pattern angles, with little visible curl shape on the head when dry. This is the most frequently mis-typed of all the curl patterns. Wearers are routinely told they have 4C because no coil is visible; the actual diagnostic is the angle of the bend.
Look closely at a single 4B strand and you'll see sharp directional changes — the hair travels in one direction for 2 to 4 millimetres, then bends at a near-90-degree angle, then bends again. It's a zigzag, not a curl. The cottony, fluffy appearance comes from many strands' bends pointing in different directions, which is why 4B reads as voluminous even at moderate density.
Shrinkage for 4B runs 60–70%, and porosity skews high — the sharp bend points are where the cuticle lifts most. 4B benefits from the same heavy creams and butters as 4A, but the layering technique is different: 4B benefits from praying-hands or finger-shingling product application section by section so the bends are coated rather than agitated. Tools like denman brushes and tight clipping tend to fight the natural Z-pattern; the hair wants to do what it wants to do, and 4B's pattern is healthiest when worked with rather than reshaped.
Cleansing shampoo every 10–14 days, co-wash in between every 3–5 days, deep-condition weekly. Refresh every two days with a water-glycerin-leave-in mix if dew points are in the comfortable 35–55°F range — Sister Scientist's Erica Douglas published a dew-point chart in her 2019 "Hair Care: Glycerin & Dew Points" white paper that's the cleanest source on this for coily hair. Above 60°F dew point, drop the glycerin; below 30°F, drop it too — humectants pull moisture out of hair when the surrounding air holds less than the hair does.
4C Hair: Tightly Coiled, Cottony Texture
4C is the tightest of all curl patterns — coils 3 to 4 millimetres wide, packed so densely that the hair reads as a single cottony mass when dry. The diameter is at the lower end of the type-4 range, roughly the width of a sewing-needle eye, and the coils sit so closely together that individual coil definition isn't visible without separating the hair.
Shrinkage on 4C runs 65–75% — the highest of any curl pattern. A 4C wearer with hair that measures 30 cm wet will see roughly 8–10 cm of dry length without elongation techniques. This isn't damage. This is the strand doing exactly what the follicle shape determines it to do.
Density on 4C is typically high (often 280–320 hairs per cm²) and porosity skews high. The cuticle layer on 4C hair is the thinnest of any type — Davis-Sivasothy reports in chapter 2 of The Science of Black Hair that 4C cuticle layers can run 4–7 scales thick compared to 7–11 on straight hair, which is part of why 4C needs more moisture more often than any other pattern. There's simply less cuticle to keep moisture in.
The 4C wash-day rhythm: cleansing shampoo every 10–14 days, co-wash every 3–4 days, deep-condition weekly with heat (a hooded dryer or thermal cap lifts the cuticle and gets conditioner deeper). Heavy creams and butters work; oils alone don't (oil seals, it doesn't moisturise — the order matters, and we get to that in the LOC vs LCO section). Refresh every 1–2 days with a water-leave-in spray; 4C dries out faster than 4A or 4B between washes.
Shrinkage in Type 4: Why Your Hair Looks Shorter Than It Is
Shrinkage is the difference between your hair's wet length and dry length, expressed as a percentage. It's not a flaw. It's a property of the coil — the tighter the coil, the more the strand contracts on itself as the water leaves it, and the shorter the visible length. Within type 4, shrinkage runs as follows on undisturbed air-dried hair:
| Sub-pattern | Shrinkage % | Wet → dry example (30 cm starting length) |
|---|---|---|
| 4A | 50–65% | 30 cm → 10.5–15 cm |
| 4B | 60–70% | 30 cm → 9–12 cm |
| 4C | 65–75% | 30 cm → 7.5–10.5 cm |
These numbers come from undisturbed air-drying after a wash with no elongation product. Banding, twist-outs, braid-outs, plopping and stretched styling all reduce the visible shrinkage but don't change the underlying coil diameter — the hair is still the same shape, you're just holding it in a different position while it dries. Heat-stretching alters the bond geometry temporarily; it'll revert at the next wash unless you've used enough heat to cause damage, in which case it won't revert and that's a different problem.
The shrinkage range is also why two 4C wearers can look like they have very different hair lengths even when their actual hair is the same. A 4C head that air-dries undisturbed reads as much shorter than a 4C head that's been banded overnight — same hair, different presentation.
The Type 4 Wash-Day Routine (the Moisture-First Model)
Type 4 wash days are longer than type 2 or type 3 wash days. That's a feature, not a bug — the moisture has to get in before it can be sealed, and the geometry of the coil means each strand needs more coaxing.
The full sequence, from start to finish:
- Pre-poo (optional but recommended for 4B and 4C): 15–30 minutes of oil or conditioner on dry hair before shampooing. The oil fills the cuticle gaps before the shampoo's surfactants strip the strand, which prevents the post-shampoo "straw" feeling. Coconut, olive, and avocado oil all work; warm them slightly for deeper penetration.
- Cleanse: sulfate-free shampoo on the scalp only, lather and rinse. Once every 10–14 days for most type 4. The mid-lengths and ends get cleansed by the runoff. Aggressive scalp-only cleansing matters because over-shampooing the strand strips it faster than other types — coiled hair retains scalp oils less efficiently along its length, which the Journal of Cosmetic Science documented in a 2014 wash-frequency study.
- Co-wash (in between cleansing shampoo days): conditioner cleanse only — no surfactants. Every 3–5 days for 4A, every 3–4 days for 4C.
- Deep condition: weekly, with heat where possible. Hooded dryer, thermal cap, or a warm towel for 20–30 minutes. Davis-Sivasothy is explicit on this point: heat-aided deep conditioning produces measurably better moisture retention on type 4 than room-temperature conditioning, because the cuticle lifts under warmth and the conditioner penetrates deeper.
- Rinse with cool water: closes the cuticle and helps seal in what you've just put in.
- Leave-in conditioner: applied to soaking-wet hair section by section. Don't skip the sections — type 4 needs every section to be touched or the dry spots show.
- Layer your products in LOC or LCO order (see decision tree below). This is where most type 4 routines stand or fall.
- Style: twists, braids, bantu knots, finger coils, or a wash-and-go. Each gives a different dry result; pick one for that wash day and don't second-guess it mid-process.
The whole sequence takes 2 to 4 hours including deep conditioning time. That's normal. Compressing it generally costs you a wash day's worth of definition. We covered the universal four-step routine in the curly hair routine step-by-step, but type 4 specifically benefits from these added moisture-retention steps on top.
LOC vs LCO: Which Layering Order for Your Type 4?
LOC and LCO are layering orders for the three products that go on wet hair after the leave-in:
- LOC = Liquid (water or leave-in), Oil, Cream. Oil first, then cream on top.
- LCO = Liquid (water or leave-in), Cream, Oil. Cream first, then oil on top.
The question is which order to use, and the answer depends on your porosity-by-sub-pattern combination. Here's the decision tree:
| Sub-pattern + porosity | Use | Why |
|---|---|---|
| 4A + low porosity | LCO | Cream goes on first while cuticle is most open; oil seals after. Heavy oil under cream on low-porosity 4A creates product buildup at the cuticle. |
| 4A + medium-high porosity | LOC | A light oil "primer" before cream improves moisture lock when the cuticle naturally lifts more. |
| 4B + medium porosity | LOC | Z-bends benefit from oil getting into the bend points before the cream caps them. |
| 4B + high porosity | LOC | Same logic; high porosity needs an oil pass before anything heavier. |
| 4C + medium porosity | LCO | Cream first, oil last — 4C's tight coils need moisture from the cream to absorb before being sealed. |
| 4C + high porosity | LOC | Oil-first creates a moisture-retention barrier the cream then sits on top of; reduces evaporative moisture loss. |
If you don't know your porosity, run the float test before committing to one order — strand floats for over a minute, you're low; strand sinks in seconds, you're high. We covered the float test in detail in the low porosity curly hair routine.
The pattern that emerges from the matrix: high-porosity type 4 tends to benefit from LOC, low-porosity from LCO. Medium porosity is the middle ground where sub-pattern decides. Once you find your order, run it three wash days in a row before changing it — switching layering order every wash is the most common reason people decide their hair "doesn't respond to anything."
How Often to Wash Type 4 Hair
Type 4 hair tolerates the longest interval between washes — typically 7 to 14 days, with co-washes (conditioner cleanses) and water-only rinses in between. Coiled hair retains scalp oils less efficiently along its length, so over-shampooing strips it faster than other types. Most type 4 wearers settle into a rhythm of one cleansing shampoo every 1–2 weeks plus co-washes every 3–5 days; 4C hair often needs slightly less frequent shampooing than 4A.
There's a temptation, especially for newer naturals, to wash more often because the scalp feels oily. Two corrections to that instinct: first, scalp oil is a feature — sebum on type 4 hair is harder to distribute down the length naturally, which is why brushing technique matters more for type 4 than for other types. Second, what feels like "oily scalp" on type 4 is often product buildup from leave-ins and creams rather than sebum. A clarifying wash once every 4–6 weeks resets that without stripping.
Teri LaFlesh's Curly Like Me (Wiley, 2010) covers the wash-frequency biology specifically for type 4 in chapter 4 — her central observation is that the hair fibre on coiled hair is structurally more porous because of the bends, and the more often you cleanse, the faster the moisture loss between washes. The lower-frequency washing pattern isn't laziness or a cultural choice; it's what the hair geometry asks for.
A Founder Note
When the Zenvy team first sat down to brief this article, we kept catching ourselves writing "type 4" as if it were one thing. It isn't. One member of our community is a 4A whose hair holds a defined spiral and reads as "curly" to strangers; another is 4B who's been told her whole life her hair is 4C because she has no visible coil. They follow different routines, use different layering orders, and get genuinely different results. The single biggest lesson from putting this guide together: the three sub-patterns deserved three sections, and we built the Zenvy AI Curl Identifier partly because too many of us in this community had been mis-typed by quizzes that lumped them into one bucket.
EAV Summary Table
| Attribute | 4A | 4B | 4C |
|---|---|---|---|
| Coil diameter (mm) | 4–6 mm | sharp bends, no defined coil | 3–4 mm |
| Shape | spiral | Z-pattern bends | tightly packed coils |
| Visible curl pattern | yes (springy S) | partial | minimal — looks cottony when dry |
| Shrinkage % | 50–65% | 60–70% | 65–75% |
| Density | typically high (250–300/cm²) | typically high | typically high (often 280–320/cm²) |
| Porosity likely | medium-high | high | high |
| Moisture frequency | every 2 days | every 2 days | every 1–2 days |
| Heaviest product type tolerated | thick creams, butters | thick creams, butters | very thick creams, oils |
What to Do Next
If you're still not sure which sub-pattern you have, run a wash-no-product-no-touch air dry and either compare against the millimetre ranges in the table above or upload a photo to the Zenvy AI Curl Identifier. Once you know your sub-pattern and your porosity, the LOC/LCO matrix above tells you the layering order. Then run that routine three wash days before changing anything.
For deeper reading on the moisture-retention step, the deep conditioning curly hair guide covers what to look for in a deep conditioner for type 4, including the protein-moisture balance most marketing copy gets backwards. And if you're starting from product zero, the Zenvy type-4-friendly product collection is filtered by curl-type compatibility — every product flagged for type 4 has been tested against the moisture-first model described above.
Type 4 Hair FAQ
What's the difference between 4A, 4B, and 4C?
4A is the loosest of the type 4 patterns — coils 4 to 6 millimetres wide with a visible springy spiral. 4B doesn't form coils at all; it bends in sharp Z-patterns. 4C is the tightest, with 3 to 4 millimetre coils that read as a single cotton-like mass when the hair is dry. All three are type 4 because the strand circumference produces the tight coiling — they're distinct only in how that coiling expresses on the head.
How often should I wash type 4 hair?
Type 4 hair tolerates the longest interval between washes — typically 7 to 14 days, with co-washes (conditioner cleanses) and water-only rinses in between. Coiled hair retains scalp oils less efficiently along its length, so over-shampooing strips it faster than other types. Most type 4 wearers settle into a rhythm of one cleansing shampoo every 1–2 weeks plus co-washes every 3–5 days; 4C hair often needs slightly less frequent shampooing than 4A.
Is type 4 hair high porosity?
Type 4 hair is most often high porosity — the cuticle naturally lies less flat on coiled hair than on straight or wavy hair, which means water and product absorb quickly but escape just as quickly. This is why the LOC method (liquid, oil, cream) and LCO method (liquid, cream, oil) exist specifically for type 4 hair: both seal the moisture in. Low-porosity type 4 exists but is the minority; do the float test before assuming.
Why does my type 4 hair shrink so much?
Shrinkage is the property of the coil contracting as water leaves the strand. The tighter the coil, the more it shrinks: 4A shrinks 50–65%, 4B shrinks 60–70%, and 4C shrinks 65–75% when air-dried with no manipulation. Shrinkage isn't damage — it's the strand doing what the follicle shape determines it to do. Banding, twist-outs and stretched styling reduce visible shrinkage but don't change the coil itself.
Should I use LOC or LCO on type 4 hair?
The order depends on your porosity and sub-pattern. High-porosity type 4 tends to benefit from LOC (oil before cream, to prime the cuticle); low-porosity type 4 benefits from LCO (cream first, oil to seal). Run a porosity float test before choosing, and stick with one order for three wash days before judging the result.
