The reason curly hair shrinks is because as curly hair dries the curl pattern pulls the strand into a coiled or spiral shape, reducing the appearance of length compared to its actual stretched state. The tighter the curl pattern the more dramatic the shrinkage. Some tight coils can shrink by up to 70% or more between wet and fully dry.
When you stretch wet curls between your fingers and watch it spring back when you let go, that is shrinkage in action. It may also be the reason why you may feel like your hair isn't growing as fast as it should be.
Here's exactly what is happening, and why shrinkage matters less than you might think.
The mechanics of shrinkage
Curly hair shrinks because of its internal structure. Each strand of curly or coily hair has an asymmetrical cross-section and uneven distribution of disulphide bonds; these are the chemical bonds that give hair its shape. As your hair dries, the disulphide bonds pull the strand into its natural coil, spiral, or zigzag pattern.
Water plays a major role in this as well. When curly hair is wet, it allows the hydrogen bonds within each strand to temporarily loosen, which allows the hair to stretch out further from the natural resting shape. Then as it dries, the hydrogen bonds within the hair reforms and contracts the strands back into its resting curl pattern. This is why curly hair appears longer when wet and shorter when fully dry.
The tighter the resting curl pattern is the more it contracts when wet. Looser and wavy patterns (2A-2C) shrink relatively little. Defined curls (3A-3C) shrink more noticeably. Tightly coiled curls (4A-4C) experience the most shrinkage due to the curl pattern resting more tightly. Same length but different shape due to the resting curl pattern.
Shrinkage is not a sign of damage
The thing to remember is that shrinkage has nothing to do with health of your curls, breakage or how well your curls are growing. Curls more prone to shrinkage can be just as long, healthy and strong as curls that shrink less.
In fact, the opposite assumption is often true. Curly hair that has lost its curl pattern through heat damage, chemical processing or significant breakage often shrinks less, because the structural bonds responsible for the coil have been altered and weakened. Generally, a strong, healthy curl will have a springy shrink that is a sign that the curl pattern is intact, and your hair is behaving the way it should.
If you're trying to get an accurate measure to track your hair growth. Measure while your curl is fully stretched out as this gives a more accurate picture of actual growth.
What affects how much your hair shrinks
A few different factors influence the degree of shrinkage you'll see:
Curl pattern and tightness. As covered above, tighter coils shrink more than looser waves. This is simply hair geometry. A tightly wound spring contracts more than a loose spring
Porosity. Shrinkage happens faster and is more visible for high-porosity hair, because it absorbs and releases water quickly. Low porosity hair absorbs and releases water slower, so shrinkage happens slower, and the hair holds its shape for longer as it dries.
Moisture levels. Hair that is properly hydrated tends to have more elasticity, allowing it to stretch and spring back to shape more freely. Dry and under-moistured hair can feel stiffer and may shrink unevenly, with some sections appearing more compressed than others.
Hair density and strand thickness. Finer hair strands tend to shrink more visibly than coarser ones. Due to the structural weight pulling the curl downward as it dries.
Styling method. Several different techniques can be used to encourage curls to dry while stretched, such as; banding, braiding, twisting or using rollers. These can reduce visible shrinkage because the hair dries in an elongated position before the curl fully contracts.
Working with shrinkage instead of against it
If shrinkage frustrates you, there are practical healthy options available that cooperates with your hair’s natural structure instead of fighting it.
Stretching methods. Braid-out, twist-outs, banding and African threading all encourages hair to maintain its stretched-out position as it dries. Reducing shrinkage while still preserving your curl definition once the style is taken out.
Low manipulation styling. Styles like buns, braids, and twists can help to hold the hair in an elongated state for longer periods. These protective styles naturally minimise the day-to-day appearance of shrinkage.
Strategic blow-drying. A diffuser attachment, or a blow-dryer with a comb attachment used on low heat, can stretch hair while drying without resorting to high heat that risks damage.
Accepting it as part of the texture. The thing to always remember is that. There is nothing wrong with shrinkage, it is your curl pattern doing exactly what it's built to do. Many people find that once they stop measuring success by length retention day-to-day, the relationship with their hair becomes considerably less stressful.
The bottom line
Shrinkage is one of the most consistent features of all curly and coily hair, and one of the most misunderstood. It's not a sign of something wrong, but a confirmation that your curl pattern. Whatever it looks like is intact and structurally healthy.
Understanding exactly why your hair shrinks tends to make it less frustrating. Once you know the mechanism, shrinkage stops looking like a problem and instead becomes an indicator that your hairs curl pattern and elasticity is exactly the way it's supposed to be.
Want to understand more about how your specific curl pattern behaves? Our free Curly Hair Guide breaks down curl typing, porosity, and how to build a routine around your hair's actual structure — read it here.