You measured your hair, and the tape says shoulder length while the mirror says chin. Both are right, and that gap is exactly why most hair length charts don't work for coily hair.
The chart above does two jobs. In "Where does it fall" mode, you enter your stretched length and slide the shrinkage, and the figure shows where your hair lands stretched and where it looks like it lands as you wear it. In "When will I reach…" mode, you pick a goal, like bra strap or waist, and it tells you how many months that takes and the rough date you'll hit it. Inches or centimeters both work, and there's no email to hand over.
Hair length chart explained
The chart runs through nine landmarks, from ear at 8 inches down to tailbone at 40. Shoulder sits at 14 inches, bra strap at 22, and waist at 30. Every figure is stretched length on an average adult, measured from the front hairline, over the crown, to the ends.
Those are the same landmarks we use on our braid size chart, so the two pages agree with each other. If you plan braids at mid-back on one, you get 26 inches on both.
Why do hair length charts disagree on waist length?
Because they measure from different places. Some charts put waist length at 20 to 22 inches. Others, including ours, put it at 30. Start the tape at the nape and you'll get a much shorter number than if you start at the front hairline and go over the crown.
Neither figure is wrong, because they're measuring different paths. What matters is that you measure the way your chart does, so we tell you exactly where we start.
How to measure your hair length
Take the number stretched, on dry hair, from the front hairline. That gives you the length your hair actually is, which is the length that grows. Shrunken length is useful too, because it tells you your shrinkage.
Time: 10 min. What you need: Soft tape measure, Mirror, A second person, if you can get one.
- Start with dry hairMeasure on dry, detangled hair. Wet coils stretch and shrink differently as they dry, so a wet number won't match the next one you take.
- Measure shrunken firstWith your hair as you normally wear it, hold the end of the tape at the front hairline, run it over the crown and read where the hair ends. Write that down as your shrunken length.
- Stretch one sectionTake a section from the middle of your head and gently pull it straight, without tugging at the root. Hold the tape at the front hairline and run it over the crown to the very ends.
- Read the stretched lengthRead the number where the ends sit. This is your stretched length, the one the chart above uses.
- Enter both numbersPut your stretched length into the chart. Use both numbers to work out your shrinkage, then set the slider to match.
Measure the same section the same way every time. Different parts of your head can be different lengths, so pick one spot and stick with it.
What is shrinkage, and how do you work it out?
Shrinkage is the gap between how long your hair looks and how long it really is. As coils spring back, they pull the length up toward your scalp, so 16 inches of hair can sit like 5.
The formula is simple. Take your stretched length, subtract your shrunken length, divide by your stretched length and multiply by 100.
With 16 inches stretched and 5 inches shrunken, that's 16 minus 5, which is 11. Divide 11 by 16 and you get 68.75% shrinkage.
Published figures put shrinkage anywhere from 30% to 75%, depending on curl pattern. At those rates, a 16-inch strand can look like about 11 inches, 8 inches or just 4. The slider above runs from 0 to 80% and starts at 50%. Measure your own and set it there.
Why shrinkage hides length on type 4 hair
The tighter the coil, the more length it pulls up. So type 4 hair can grow for months and look like it hasn't moved.
Take 14 inches stretched. That lands right at shoulder length. At 50% shrinkage, it wears like 7 inches, which sits shorter than ear. You'd swear your hair was a bob. It isn't, it's at your shoulders, and you'll see it the day you stretch it.
That's why we track stretched length. It's the number that actually grows.
How long does it take to grow from one length to another?
Count the inches between where you are and where you want to be, then divide by half an inch a month.
- Shoulder to bra strap: 14 to 22 inches is 8 inches, so about 16 months.
- Bra strap to waist: 22 to 30 inches is another 8 inches, so another 16 months.
- Shoulder to waist: 14 to 30 inches is 16 inches, so about 32 months. That's a little under three years.
The chart above does this for you in "When will I reach…" mode. Pick your goal, and it gives you the months and a rough date. If your own hair grows faster or slower than half an inch, you can set the rate anywhere from a quarter inch to three quarters of an inch a month.
Do trims slow you down?
Yes, and by more than most people think. Trim a quarter inch every 8 weeks and your net growth drops from 0.5 inches a month to about 0.36.
That turns shoulder to bra strap from 16 months into about 22, six extra months for the same goal.
None of this means you should stop trimming, only that you should know the trade-off before you book the next one. Trims are off by default in the chart. Switch them on to see the timeline with a quarter inch off every 8 weeks.
Wig length chart: why wigs fall longer
Wigs are measured from the crown, not the front hairline. So a wig sold at a certain length falls longer than the same inches of your own hair.
On your own head, the first few inches of every strand travel from the hairline back over the top of your head before they ever start falling. A wig skips that stretch. All the inches it's sold at hang down from the crown.
So don't match a wig to a landmark on our chart inch for inch. A wig will land lower on your body than your own hair at the same number. When you're choosing a wig length, pick shorter than your landmark suggests.
Braid and extension lengths
Braid lengths are sold using the same landmarks: shoulder, bra strap, mid-back, waist. Our braid size chart uses the same inches as this page, from chin to tailbone.
Use this chart to see where a length lands on you, then switch to the braid planner. It turns a size and a length into a braid count, how many packs of hair to buy and how long the install takes.
Tracking your child's hair growth
Parents doing a child's hair are our biggest group of customers, so the chart has a "For my child" switch. It changes the copy and the product picks. It doesn't change the landmarks.
Here's why: on a smaller body, every landmark sits higher. Your child's shoulders are closer to their crown than yours are to yours. So the same inches fall lower on your child than they would on you.
Measure your child the same way you'd measure yourself: dry, stretched, from the front hairline over the crown. Write the number down every couple of months. Kids' hair shrinks just like adults' does, so a stretched number is the only fair way to see progress.
Length retention: breakage is where length goes
Your hair is growing. If it doesn't seem to get longer, the length is breaking off at the ends about as fast as it grows at the roots. Retention is the whole game.
Most breakage happens at three moments: detangling, styling and sleeping. Detangle on wet hair with conditioner in, working from the ends up to the roots. Rough towels and rough brushes snap coils, so go gentle on both. Cover your hair at night so it isn't rubbing on cotton while you sleep.
Fifty of the 2,012 reviews of our WonderBrush mention breakage. Here are three of them:
"My beautiful granddaughter , whose waist length hair( when wet, of course) has ALWAYS left piles of hair in the shower. With this brush there is not even a strand of hair . Amazing!!!! She used to hate to brush her hair now she spends a great deal of time doing so. Thank you!" JoAnn S.
"I love it! After I did a co-wash, I used it and my hair combed without minimal breakage! I suffered from extreme shrinkage after a wash of any kind, so this is great to have and made it easier for more to do twists in my hair!" Adar J.
"My son and I have slightly different levels of curliness to our hair. We're both multi racial. This brush is phenomenal! We have SO MUCH LESS BREAKAGE!" Michelle H.
At night, a satin sleep bonnet keeps your ends off the pillowcase. After washing, squeeze the water out with a microfiber towel instead of rubbing. If you deep condition with heat, our hair porosity test tells you how long to leave it on.
Frequently asked questions
Sources
The half-inch-a-month growth rate, the 30 to 75% shrinkage range, the shrinkage formula and the point that wigs are measured from the crown come from published hair length charts, hair growth calculators and a shrinkage calculator, read October 10, 2026. The landmark inches come from published hair length and braid length charts, and they match our braid size chart. The breakage count and the three reviews are from our own WonderBrush reviews.
Measure your hair stretched, put the number in the chart above, and see exactly how close you are to your next length.