Question 1

How does the AI compare two faces?

Accepted Answer

It detects one face per image, aligns each face using 68 facial landmarks, encodes each aligned face as a 128-dimensional vector with a FaceNet-style ResNet, and computes cosine distance between the two vectors. Cosine distance is mapped to a friendly 0–100% similarity score. All inference is JavaScript in your browser via @vladmandic/face-api on TensorFlow.js.

Question 2

What does the percentage actually mean?

Accepted Answer

It is a smooth mapping of cosine distance to a 0–100 scale. In rough terms: 90–100% = visually nearly identical (same person, twins, or an extreme lookalike); 70–90% = same person likely, or close relatives; 50–70% = some shared features but not necessarily the same person; below 50% = different people. It is NOT a probability and it is NOT a biometric verification result.

Question 3

Why do unrelated people score 60%?

Accepted Answer

Because the descriptor encodes the broad shape of the face — eye spacing, nose width, jaw angle, ethnicity, age — and many unrelated people share enough of those features to land in a similar region of the embedding space. This is a fundamental property of 128-d face descriptors, not a bug.

Question 4

Why did my own photo score only 75% against another photo of me?

Accepted Answer

Common causes: (1) different lighting or camera angle; (2) different age (more than a few years can shift descriptors meaningfully); (3) glasses or facial hair in only one of the photos; (4) heavy filters or FaceTune in one photo; (5) one photo is much lower resolution; (6) you are wearing makeup in one and not the other. Try another pair of photos with similar conditions.

Question 5

Are my photos uploaded?

Accepted Answer

No. All face detection, encoding, and comparison happens locally in your browser via TensorFlow.js. The model weights are downloaded once (about 6 MB, cached) and the inference runs on the JPEGs you select. Photo bytes never leave the device. We don't store, log, or share photos.

Question 6

Can I use this for identity verification?

Accepted Answer

No. Do not use this tool to verify someone's identity, gate access to a service, prevent fraud, or screen employees / dates. It has no liveness detection, no calibrated threshold, no demographic fairness audit, and uses a smaller open-source model than commercial systems. For identity verification you need a vendor evaluated under NIST FRVT with documented FAR/FRR and operational guarantees.

Question 7

Why are identical twins not distinguishable?

Accepted Answer

The face descriptor is trained to be invariant to lighting, expression, and pose, but is not designed to capture micro-features that even humans use to tell twins apart (small mole, slight asymmetry). Twin-discrimination is an active research area; standard face encoders generally fail at it.

Question 8

Can it tell parents and children apart?

Accepted Answer

Often, but not always. Parents and adult children share many genetic facial features and may score 60–80%. The model is trained to put the same identity close together, but it has no notion of 'family resemblance' versus 'identity', so high scores between relatives are common and expected.

Question 9

Does it support multiple faces in one photo?

Accepted Answer

Currently it picks the single most confident face per image and compares those two. If your photos are group shots, crop each one to a single face first. For multi-face workflows we have a dedicated Age & Gender Predictor that iterates over every detected face in an image.

Question 10

What if no face is detected?

Accepted Answer

The tool reports 'no face detected' for that image. Common causes: face is too small (below detector minimum size), face is at an extreme angle, lighting is too dark or too bright, image is heavily blurred, or the image is not actually a photo of a face. Try a clearer, larger, frontal photo.

Fahrenheit (°F)	Kelvin (K)
32°F	273.15K
50°F	283.15K
68°F	293.15K
86°F	303.15K
104°F	313.15K
122°F	323.15K
140°F	333.15K
158°F	343.15K
176°F	353.15K
194°F	363.15K
212°F	373.15K

Fahrenheit to Kelvin Converter

How to convert Fahrenheit to Kelvin?

Example

What is 32°F in Kelvin?

What is 212°F in Kelvin?

What is Kelvin?

Popular Fahrenheit to Kelvin conversion table