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Hair Length Converter (cm ↔ inches)

Name: How to use the Hair Length Converter
Uploaded: 2026-11-07
Duration: 49 s
Description: A short walkthrough of converting hair length from centimeters to inches and back, and finding the matching length level and bundle length.

Convert hair length from cm to inches and back — fractions welcome — and see which length level it reaches on you or which extension length to buy.

Length

Type 30, 12.5, 12 3/8 or 45 cm — fractions and units are fine.

Convert from

Inches → cmcm → inches

Common lengths

Your height

Used to show which length level this reaches on you.

In centimeters

30.5 cm

12″ = 30.48 cm

Inches

12″

Tape measure

12″

nearest ⅛ in

Centimeters

30.5 cm

Nearest hair length sold

12″

standard length

On a 5′4″ frame, 12″ of stretched hair reaches about shoulder length — 3″ (7.6 cm) short of armpit length.

Hair is often said to grow about ½″ (1.27 cm) a month, but real rates vary from person to person. Estimate how long your next level will take →

See where this length falls on your bodyOpen the length chart scaled to your height

How to use the Hair Length Converter (cm ↔ inches)

Type a length

Enter any hair length in the Length box — decimals, fractions like 12 3/8, or a value with a unit such as 45 cm all work.
Choose the direction

Pick “Inches → cm” or “cm → inches”, or tap ⇄ Swap to flip the result. A unit you type always wins.
Read the result

You get the converted length, the nearest ⅛ inch for a tape measure, and the nearest standard length sold for bundles, wigs and braiding hair.
Add your height

Choose your height to see which length level — shoulder, armpit, bra-strap and so on — that length reaches on you.

How to use the Hair Length Converter (49 s)

How the hair length converter works

The conversion itself is exact: one inch is defined as precisely 2.54 centimeters. The converter multiplies inches by 2.54 to get centimeters and divides centimeters by 2.54 to get inches. Everything else on this page is there to make that number useful when you are measuring your own hair or buying extensions.

Fractions and tape measures

Most U.S. tape measures are marked in eighths of an inch, so the result is also shown rounded to the nearest ⅛″. You can type fractions the same way you read them — 3/8, 12 3/8 or 12-3/8 — and you can add a unit to what you type (45 cm, 16 in, 16″). A typed unit wins over the toggle until you change the toggle yourself.

Which length level is it?

Length levels such as shoulder length (SL), armpit length (APL) and bra-strap length (BSL) are measured on stretched hair, from the crown down the back. They are drawn for a 5′4″ frame and scaled to the height you pick, because a longer torso places every level a little lower. Treat the level as a guide — shoulders, bra straps and waists sit in slightly different places on everyone.

Extension and bundle lengths

Hair for bundles, wigs and pre-cut braiding is sold in even-inch steps, usually from 8″ to 30″ and in longer lengths from some sellers. The converter shows the nearest of those standard lengths. When a value sits exactly between two, it suggests the longer one, since hair can be trimmed but not added back. Remember that curly textures are measured stretched and will look shorter once installed.

Measuring your own hair

Measure from the crown (the top of your head) down the back to the ends of a section that is gently stretched, not pulled tight.
For coily hair, stretched and shrunken lengths can differ by half or more — note which one you measured.
Use the same spot and method each time if you are tracking growth, so month-to-month numbers are comparable.

Hair length conversion chart: 2″ to 40″

Inches	Centimeters	Level at 5′4″	Sold as standard length?
2″	5.1 cm	Shorter than ear length	—
4″	10.2 cm	Shorter than ear length	—
6″	15.2 cm	Ear length	—
8″	20.3 cm	Ear length	Yes
10″	25.4 cm	Chin length	Yes
12″	30.5 cm	Shoulder length	Yes
14″	35.6 cm	Shoulder length	Yes
16″	40.6 cm	Armpit length	Yes
18″	45.7 cm	Bra-strap length	Yes
20″	50.8 cm	Bra-strap length	Yes
22″	55.9 cm	Mid-back length	Yes
24″	61 cm	Mid-back length	Yes
26″	66 cm	Waist length	Yes
28″	71.1 cm	Waist length	Yes
30″	76.2 cm	Hip length	Yes
32″	81.3 cm	Hip length	Yes
34″	86.4 cm	Tailbone length	Yes
36″	91.4 cm	Tailbone length	Yes
38″	96.5 cm	Classic length	Yes
40″	101.6 cm	Classic length	Yes

Levels measured from the crown on stretched hair for a 5′4″ frame. Standard lengths are the even-inch steps most bundle, wig and braiding-hair sellers use.

Frequently asked questions

How many inches is 30 cm of hair?

30 cm is 11.81 inches — just under 12 inches, or about 11¾″ on a tape measure. On an average 5′4″ frame that is close to shoulder length when measured stretched from the crown.

How many inches is 50 cm hair?

50 cm is 19.69 inches. If you are shopping for extensions, the nearest standard length is 20″.

How many centimeters is 14 inch hair?

14 inches is 35.56 cm. To convert any length, multiply inches by 2.54; to go back, divide centimeters by 2.54.

Is 12 inches of hair shoulder length?

For many women around 5′4″, yes — about 12 inches from the crown reaches the shoulders when the hair is stretched. Taller people need a little more length to reach the same point. The length chart shows the levels scaled to your height.

How are bundle and wig lengths measured?

Sellers measure the hair itself from the weft or lace to the ends, held straight. Curly and wavy textures are usually measured stretched, so they look shorter once they are worn. Where the hair falls on your body also depends on where it is attached — a part at the crown sits higher than a track at the nape.

Why does my 20-inch wig look shorter than 20 inches?

Usually because the length is measured stretched and the texture has curl or wave, because part of the length goes over the top of your head before it hangs, or because your torso is longer than the frame the seller pictured. Measure from the crown down your back to see where 20″ will actually land.