Free · runs on your device
Jawline rating
Your gonial angle and jaw-to-cheekbone ratio, estimated from facial landmarks. Measured geometry plus the honest levers — body fat and posture move a jawline more than any gadget.
CostFree
TimeUnder 1 min
SignupNone
DataStays on device
478-point landmark map
Step 1 of 2 · your photo
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Face the camera straight on, hair off the face, even light, no tilt.
How it works
Add your photo
Camera or upload — either works.
Mapped in your browser
478 landmarks, entirely on your device.
Your measured result
Numbers and lines drawn on your photo.
On-device · never uploaded
478 landmarks
Free · no signup
The science
Jaw geometry: what the gonial angle actually tells you
01
The gonial angle is the angle at the corner of your jaw, where the vertical ramus meets the horizontal body of the mandible. In cephalometric studies it typically measures around 120–130°; a lower angle reads as a sharper, more “defined” jaw corner, a higher one as a softer transition. This tool estimates the angle on each side from facial landmarks and also reports your jaw-to-cheekbone width ratio, which is the other half of how defined a jawline looks.
02
A front-facing photo can only estimate a 3D angle, so treat the number as an estimate with a few degrees of tolerance — and shoot straight-on, since a turned head shows one side at a flattering angle and the other unfairly. Left and right differing by several degrees is normal mandibular asymmetry.
03
The honest levers, in order of effect: body-fat percentage dominates jawline visibility for most people (submental fat softens the outline regardless of bone); posture — forward head position blurs the neck-jaw boundary; and bone geometry, which is genetic. Mewing and jaw-exercise gadgets have no credible evidence for changing adult bone structure.
Your gonial angle, in context
Cephalometric norms put the adult gonial angle around 120–130°, and the whole range reads normal in faces: lower angles (sharper corner) photograph as "defined" or "chiseled"; higher angles blend the jaw into the neck line more gradually and read softer. Sex and ancestry shift the distribution several degrees, angles increase slightly with age and tooth loss, and the left-right difference this tool reports separately is typically a few degrees in everyone. A front-facing photo estimates a 3D angle, so treat your numbers as a band, not a decimal.
The jaw-to-cheek ratio is the second half of the read: a jaw nearly as wide as the cheekbones photographs "strong" regardless of the angle; a narrower jaw shifts the face toward heart or diamond classification and takes styling (collar shapes, beard lines, hair volume) that adds lower-face width if you want it.
The jawline improvement hierarchy, ranked by evidence
Body-fat percentage dominates: submental fat obscures the mandible outline no matter the bone, and jawlines routinely "appear" during modest overall fat loss — no spot-reduction required, none exists. Posture is second: forward-head position compresses the jaw-neck angle, and simply leveling the head restores definition in photos instantly. Third, styling: beard lines cut at or above the natural jaw sharpen the read; hair volume rebalances proportions. The gadget tier — jaw exercisers, chewing gum protocols, mewing — has no credible evidence for changing adult bone, and masseter hypertrophy from heavy chewing widens the jaw *corner* muscle, which is a different look than definition and a cause of jaw pain. In-clinic, masseter Botox slims a wide muscular jaw and chin filler or submental fat reduction address structure — dermatologist territory.
FAQ
Common questions
What is a good gonial angle?+
There is no “good” — typical is roughly 120–130°. Lower angles look more angular, higher angles softer; both are normal anatomy, and lighting or a slight head turn changes the visual impression more than a few degrees of bone ever will.
How can I get a more defined jawline?+
In order of evidence: reduce overall body fat if you carry fat under the chin, fix forward-head posture, and accept that the rest is skeletal. Chewing gadgets and mewing lack evidence for changing adult bone.
Why do my two sides measure differently?+
Everyone’s mandible is asymmetric to some degree, and a slightly turned head exaggerates it in a photo. A difference of a few degrees is expected; reshoot straight-on before reading anything into it.
What gonial angle is considered attractive?+
Preference studies cluster around the middle of the normal band (~120–125°) for male-typed "definition" reads, but ratings vary more with the fat and posture over the bone than the bone itself. There is no target number worth pursuing.
Why is one side of my jaw sharper?+
Mandibular asymmetry plus habitual chewing side — the usual masseter is slightly larger. A few degrees of left-right difference is universal; photos taken slightly turned exaggerate it further.
Does chewing gum give you a jawline?+
It trains the masseter like any muscle — which thickens the jaw corner over months of heavy use and can cause TMJ pain. That widening is not the "defined jawline" look, which is about low submental fat and the mandible border, not muscle bulk.