Cephalic Index Calculator

The Cephalic Index is a measurement used in anthropology and medicine to describe the shape of a human skull — specifically how round or elongated it is relative to its length. Enter the Maximum Length of Head (front to back) and Maximum Breadth of Head (side to side), then select your measurement unit (mm, cm, or inches) to get your Cephalic Index, Skull Classification (e.g. dolichocephalic, mesocephalic, or brachycephalic), and Breadth to Length Ratio.

mm

Measure from front to back of skull at widest point

mm

Measure from side to side at widest point

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Cephalic Index

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Skull Classification

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Breadth to Length Ratio

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Frequently Asked Questions

What is a Cephalic Index?

The cephalic index is a numerical value that describes the shape of the head by comparing the maximum breadth to the maximum length. It's calculated as (breadth/length) × 100 and used in anthropometry and medical assessments.

How to Calculate Cephalic Index?

To calculate the cephalic index, divide the maximum breadth of the head by the maximum length, then multiply by 100. The formula is CI = (Breadth / Length) × 100.

What do different cephalic index values mean?

Values below 75 indicate dolichocephalic (long head), 75-83 indicates mesocephalic (medium head), and above 83 indicates brachycephalic (broad head). These classifications help describe skull shape variations.

How do I measure head length and breadth accurately?

Use calipers or a measuring tape. For length, measure from the most prominent point of the forehead to the back of the head. For breadth, measure the widest part from side to side above the ears.

Is the cephalic index used in medical diagnosis?

Yes, the cephalic index is used in medical fields including pediatrics, neurosurgery, and anthropology to assess skull shape and detect potential abnormalities like craniosynostosis.

What is a normal cephalic index range?

A normal cephalic index typically ranges from 75 to 85 for most populations, though there can be natural variation based on ethnicity and individual genetics.

Can the cephalic index change with age?

The cephalic index is relatively stable after early childhood. In infants, skull shape can change due to growth and positioning, but adult measurements remain fairly constant.

What units should I use for measurements?

Any consistent unit works (millimeters, centimeters, or inches) since the cephalic index is a ratio. However, millimeters are commonly used in medical settings for precision.