How the gonial angle is measured
Dentists and orthodontists measure the gonial angle on a side-view skull X-ray. They draw one line along the back edge of the vertical jaw bone (the ramus) and another along the lower edge of the jaw (the mandible body). The angle where they meet is the gonial angle.
Many studies report adult averages in the region of 120 to 130 degrees, but it varies with age, sex and population. Because it is measured in 3D bone, a front-facing photo can only give an approximation of how sharp the jaw looks.
What a sharper or wider angle looks like
| Angle | How the jaw tends to look |
|---|---|
| Smaller (sharper) | More angular, a defined corner at the jaw |
| Larger (wider) | Softer, more rounded jaw corner |
What affects the angle
- Genetics and bone structure. The main factor, and it is fixed in adults.
- Age. The angle changes through growth and can change later in life.
- Teeth and bite. Tooth loss or changes in chewing can alter the shape of the jaw over time.
- Muscle. The chewing muscle (masseter) adds visible width at the jaw corner.
What you can and cannot change
Everyday habits do not change the bone angle itself. What does change is how defined the jawline looks, through facial leanness, posture, hydration and sleep. Tongue-posture techniques often called mewing are popular in looksmaxxing communities, and Hexum’s daily protocol includes posture checks. Rescan to see whether your jawline score changes. Any surgical option is a medical decision to take up with a qualified professional.
Hexum measures jawline definition from a front-facing photo and scores it from 0 to 100, alongside the rest of its 34 metrics. Read the full jawline analysis guide for what to work on.
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