Face analysis tools look simple: you add a photo and get an age, a face shape or a score. Behind that is a small piece of machine learning that finds a face and measures it. This guide explains how it works, how far you can trust it and where to be careful, using our face age detector, face shape detector and face symmetry test.
How the tools work
- Find the face. A small neural network looks for faces in the picture and draws a box around each one.
- Place landmarks. A second model puts 68 points on the face: the jaw line, eyebrows, eyes, nose and mouth.
- Measure. The tool compares distances between the points. Face shape uses ratios, symmetry mirrors points across a midline, and age uses a third model trained on photos with known ages.
All of this runs in your browser. Your photo is not sent to a server, and only the model files are downloaded the first time.
How accurate are they?
- Age: usually within a few years in good conditions, but it can be off by 5 to 10 years or more. Light, makeup, expression and image quality all matter.
- Face shape: a rough guide. The landmark model describes the main parts of a face well but the jawline only roughly.
- Symmetry: reacts to real differences between the two sides, but also to head tilt, a smile and the lens.
Getting a better photo
- Face the camera straight on and keep the head level.
- Use soft, even light and avoid strong shadows.
- Keep a neutral expression with the mouth closed.
- Pull hair away from the face and remove glasses if you can.
- Stand a little back and use a normal lens, not a very wide one.
Use them responsibly
- Do not use an age estimate to decide if someone is old enough for anything.
- Do not use these tools to rate, rank or judge people.
- Only use photos of people who have agreed to it.
- Remember that a number from a model is an estimate, not a fact about a person.
Frequently asked questions
Can these tools identify who someone is?
No. They only measure shapes in a photo. They do not recognise or match people.
Is attractiveness something a tool can measure?
No. Symmetry and proportions are only two things among many, and beauty depends on culture, context and personal taste. That is why our symmetry test does not claim to rate attractiveness.
Why do I need an internet connection?
The face model files, about 1 MB, are downloaded from a public CDN the first time you use a tool. Your photo itself stays on your device.
Free, runs in your browser, nothing uploaded, no sign-up.
Keep reading
More from Image & Photo Tools.
Tools for this job
Free, in your browser, no sign-up.
Bulk Image Compressor
Background Remover
Image Cropper
Face Age Detector
