Curl shrinkage calculator: how long is my hair really?
Curls hide length. Measure a curl stretched and as it sits, and see your shrinkage, how it compares, and how long your hair really is.
What hair shrinkage is
Shrinkage is the difference between how long your hair is when it is stretched straight and how long it looks when it curls. A strand that is 12 inches long but sits at 6 inches has 50% shrinkage. The tighter the curl, the more length goes into the spiral.
| Curl type | Typical shrinkage | Example: 12 in stretched sits at |
|---|---|---|
| 2A to 2C | 5 to 20% | 9.5 to 11.5 in |
| 3A to 3B | 25 to 40% | 7 to 9 in |
| 3C | 40 to 55% | 5.5 to 7 in |
| 4A | 50 to 65% | 4 to 6 in |
| 4B to 4C | 65 to 80% | 2.5 to 4 in |
How to measure it
- Start with clean, dry hair with no product, so nothing is weighing the curls down or holding them up.
- Pick a curl at the crown. Measure from the scalp to the tip as it sits: that is the curled length.
- Gently pull the same curl straight without tugging and measure again: that is the stretched length.
- Shrinkage % = (stretched − curled) ÷ stretched × 100.
Is shrinkage bad?
No. Shrinkage means the hair is elastic and holding moisture. Hair that suddenly stops shrinking and stays limp and stretched is often over-processed or needs protein. If you want to show length for an occasion, stretch it with heatless methods first, and use low heat with a protectant if you use a dryer.
Read next
- Growing out curly hair: a month-by-month guide to the awkward stage
- What’s my curl type? The 2A–4C chart, explained in plain words
- 4C hair routine: moisture, low manipulation and length retention
Questions people ask
How do you calculate hair shrinkage?
Measure a curl stretched and as it sits. Subtract the curled length from the stretched length, divide by the stretched length and multiply by 100. For example, 12 in stretched and 4 in curled is 67% shrinkage.
How much does 4C hair shrink?
4C hair commonly shrinks 70 to 80%. Hair that reaches the middle of the back when stretched can sit at chin length.
Does shrinkage mean healthy hair?
Usually, yes. Shrinkage shows good elasticity and moisture. A sudden loss of shrinkage, with limp, stringy curls, can mean heat damage or a need for protein.
How can I reduce shrinkage?
Stretch the hair while it dries: banding, twist-outs, braid-outs, African threading, or diffusing upside down. Heavier stylers also weigh curls into a longer shape.