What does an AI face analysis actually measure?
Short answer: FaceTwin’s AI face analysis places 68 landmarks on one selfie and measures symmetry, golden-ratio proportions, facial thirds, canthal tilt, jaw angle and face shape. Each trait is explained and compared with 1,196 reference faces (median score 7.2). Free, no sign-up, and it runs in your browser, so the photo is never uploaded.
A good AI face analysis measures geometry you can check, not a hidden opinion. FaceTwin’s model finds your face and places 68 landmarks on the brows, eyes, nose, lips and jawline. From those points it measures six traits: left–right symmetry across 26 landmark pairs, seven golden-ratio proportions, the balance of the middle and lower facial thirds, the canthal tilt of both eyes in degrees, the angle at the corners of the jaw, and your face shape. Five of them are combined into a 1–10 proportions score — symmetry 30%, golden ratio 20%, thirds 20%, tilt 15% and jaw 15% — and every part is shown next to the median of 1,196 reference faces, so you see where you sit instead of a bare number. The whole analysis runs in your browser and the photo is never uploaded. It is entertainment, not a measure of worth.
- 68 landmarks, 6 measured traits
- Score weights: 30/20/20/15/15
- Median score in 1,196 faces: 7.2
- In-browser; the photo stays on your device
How to use it
- Upload a selfie or take one: a front-facing, well-lit photo of yourself, no glasses, neutral expression.
- Wait a few seconds: the face model finds 68 landmarks in your browser; the photo is not uploaded.
- Read your 1–10 score and the six explained measurements.
- Try two more photos and average them for a steadier result.
Go deeper on each measurement
The six traits in one table
Most “AI face analysis” apps return one score and a paywall. Here is everything FaceTwin measures, how it is measured and what is typical, so you can read your own result in context.
| Trait | How it is measured | Typical value (1,196 faces) |
|---|---|---|
| Symmetry | 26 left–right landmark pairs mirrored across the midline | Median 79%; 17% reach 90%+ |
| Golden ratio | Seven ratios compared with 1.618 or 1:1 | Median score 77 |
| Facial thirds | Middle third (brow → nose base) vs lower third (nose base → chin) | Median score 75; lower third longer in 15.8% |
| Canthal tilt | Angle from inner to outer eye corner, head levelled first | Median +3.5°; 70.2% neutral |
| Jaw angle | Average angle at both corners of the jaw | Median 145.9°; 63.2% balanced |
| Face shape | Length-to-width and jaw-to-cheekbone ratios plus jaw angle | Oval 52%, diamond 3.8% |
The first five traits feed the 1–10 proportions score. Face shape is descriptive only: no shape scores higher than another.
How to read your score
| Score | Where it sits among 1,196 reference faces |
|---|---|
| 8.0 and above | Top 10% — very even, close-to-classical proportions |
| 7.2–7.9 | Above the median |
| 6.4–7.1 | Below the median but inside the middle 80% |
| Below 6.4 | Bottom 10% of the reference set — often caused by angle or light |
The reference faces are public figures photographed by professionals, so they are not an average of everyone. A score a little below their median is ordinary. Look at the individual traits: they tell you more than the total, and two of them — tilt and jaw — move a lot with the camera angle.
AI face analysis apps compared
| FaceTwin | Typical upload-based face analysis app | |
|---|---|---|
| Where the AI runs | In your browser | On the app’s server |
| Photo uploaded? | No | Yes, usually stored for an unstated time |
| What you get | Six traits, each with a number, a meaning and a median | One score, details behind a paywall |
| Same photo, same result? | Yes — the measurement is deterministic | Often not, especially for generative “AI ratings” |
| Price | Free | Often a trial that becomes a weekly subscription |
Get a reliable analysis in four steps
- Face the camera straight on at eye level. Tilting the phone up or down changes the facial thirds and the jaw angle more than anything else.
- Use even daylight from the front. Side light creates shadows that shift landmarks on one side and lower symmetry.
- Keep a neutral expression with your mouth closed, and move hair away from the brows and jaw.
- Run two or three photos and look at the traits that stay the same. Those are your real proportions; anything that jumps is the photo.
What an AI face analysis cannot tell you
- How attractive people find you. Attraction depends on expression, voice, style, familiarity and taste, none of which a still photo measures.
- Your health, personality, intelligence or ancestry. FaceTwin does not estimate any of these, and no landmark model can do it reliably.
- Your age or identity. The analysis is about proportions only and never tries to recognise who you are.
Treat the result as a curious look at geometry. It is for adults using their own photo, and it is entertainment, not a measure of worth.
Frequently asked questions
Is this AI face analysis free?
Yes. All six measurements, the 1–10 score and the explanations are free, with no account, ads or trial. Only the optional AI portraits and style reports are paid.
Does the AI upload my face?
No. The face model runs in your browser, so the photo, the 68 landmarks and every measurement stay on your device. It even works in airplane mode after the model has loaded.
How accurate is AI face analysis?
The landmark positions are accurate to a few pixels on a sharp, front-facing photo, so ratios repeat well. Camera angle and lens distortion matter more than the AI; use eye-level photos taken from arm’s length or further.
Why is my score different on another app?
Apps weight different traits, use different reference sets, and some generate a score with a language model rather than measuring. FaceTwin publishes its weights and its medians so you can compare like with like.
Can I analyse someone else’s face?
Only an adult who has agreed to it. The tool is built for looking at your own photo; do not use it to rate strangers or classmates.
Is my photo uploaded?
Not for local lookalikes or face analysis: the model runs in your browser, so your selfie, landmarks and descriptor stay on your device. AI portraits, including the first free one, and full reports send your photo through our server to the AI provider after a free first-portrait request or a credit purchase, and separate upload consent. Reports also send your numeric measurements. FaceTwin does not save the original photo; it is discarded from request memory after processing.
More from the same selfie
Related by topic
Face proportions
The data behind the scores: FaceTwin facts · face shape statistics
Last updated 2026-10-18. FaceTwin is for entertainment and is not identity recognition, medical or cosmetic advice.