Facial Emotion & Expression Recognition API

Facial Expression Intelligence – Not Just Emotion Labels

Real-time emotion, attention, and micro-expression data from a single API.

FacialProof converts facial movement and gaze into measurable behavioral signals that your software can act on instantly, utilizing micro-expressions with a 468-point 3D model to deliver structured behavioral data in milliseconds.

👁️ Facial recognition

Choose a demo portrait or capture a new photo, then review detections and explore the API request builder.

Reference image

Use a preset below or open the camera. Faces are detected on the image you select.

Reference image

Demo faces

Results & API

Live face data from Human.js on your image. Request / Response tabs are a sample API explorer only.

200 OK Time: 245ms Size: 2.3 KB
{
  "success": true,
  "faces_detected": 3,
  "faces": [
    {
      "id": 1,
      "confidence": 0.95,
      "bounding_box": {"x": 150, "y": 200, "width": 300, "height": 350},
      "age": "27-29 years old",
      "emotion": "Happy",
      "gender": "Female"
    },
    {
      "id": 2,
      "confidence": 0.92,
      "bounding_box": {"x": 500, "y": 180, "width": 280, "height": 320},
      "age": "25-27 years old",
      "emotion": "Neutral",
      "gender": "Male"
    },
    {
      "id": 3,
      "confidence": 0.88,
      "bounding_box": {"x": 800, "y": 250, "width": 200, "height": 250},
      "age": "6-8 years old",
      "emotion": "Happy",
      "gender": "Male"
    }
  ]
}

🔒 Liveness & ID verification

Upload your ID, start the camera, then follow the on-screen steps to verify it’s really you.

Ready to start. Upload your ID card image and start the camera.

ID card

Use a clear photo of your ID card. The face on the card will be compared to your live camera feed. You can also drag and drop an image here.

📤

Drop ID image here

or

Live camera

Start the camera first. You’ll match your face to the ID, then complete head turns and the number challenge.

🔒 Liveness Detection
Please follow the instructions below
1
2
3
4
Starting verification…
Click “Start Camera” to begin

Verification results

ID image Waiting upload
Liveness Not started
Face similarity
Decision Pending

🎭 Facial Emotion Recognition

Upload an image or use real-time camera for face shape analysis using advanced AI

Upload an image or start camera to begin face detection
📤

Drop image here

or

Face Shape

Upload an image or start camera to detect face shape

Personal Attributes

Gender
Age
Primary Emotion
All Emotions
Face Angle

Face Measurements

Face Width
Face Height
Width/Height Ratio
Jaw Width
Forehead Width

Detection Info

Faces Detected 0
Confidence
Processing Time

🎤 Speech emotion recognition

Record a short sample (~3 seconds). We’ll show waveform, spectrum, and predicted emotions.

Click to start recording (3 seconds)
Audio waveform
Frequency spectrum

Go beyond identity • Decode intent, mood, and engagement SDKs for Python, JS, Mobile

Turn Human Expressions into Actionable Insights

Most AI systems identify who a person is. FacialProof tells you how they feel, moment by moment.

Our Facial Emotion Recognition API uses advanced affective computing and a high-density 3D facial model to extract real-time sentiment, attention, and expression data from video or images.

Upload an image via API

Real-Time Sentiment AI

Instantly detect core emotional states and their intensity as they change, ideal for live interactions, feedback loops, and adaptive UX.

Face detection & validation

Micro-Expression Detection

Capture involuntary facial reactions that last only milliseconds, often revealing true responses before conscious control kicks in.

Receive structured results

Attention & Gaze Tracking

Understand exactly where users look, when focus drops, and what visually engages them most.

Receive structured emotional metrics (not vague labels) that can be logged, scored, and acted on programmatically.

Advanced Facial Expression Recognition – Built on Precision

FacialProof is built on a 468-point 3D facial landmark mesh, enabling ultra-granular tracking of facial muscle activity in real time.
This approach aligns with the Facial Action Coding System (FACS), the scientific standard developed from the research of Paul Ekman.

Real-Time Emotion & Mood Detection

Detect the full emotional spectrum — including neutral and mixed states — as expressions evolve frame by frame.

Tracked emotional states:

  • Happiness
  • Sadness
  • Anger
  • Fear
  • Surprise
  • Disgust
  • Contempt
  • Neutral / Transitional states

Each emotion is delivered with confidence and intensity scores, allowing you to quantify engagement instead of relying on binary labels.

Gaze & Attention Tracking API

Understand visual attention, not assumptions.

FacialProof tracks eye direction and fixation patterns to determine where users are looking — and when their attention drifts.

Perfect for:

  • Accessibility tools and hands-free interaction systems
  • UX & usability research
  • Ad creative testing and attention heatmaps

High-Resolution Expression Metrics

Capture subtle facial movements that traditional models miss.

Using high-density landmark tracking, FacialProof detects micro-level facial changes with sub-pixel precision.

Measured expression signals include:

  • Brow tilt, raise, and tension
  • Eye closure, squinting, and asymmetry
  • Mouth opening, compression, and smirks
  • Cheek activation and jaw movement

This allows you to distinguish between genuine reactions and socially masked expressions.

Real-World Applications of Expression AI

Measure real emotional response — not opinions.

Market Research & Retail

See how people actually react to ads, products, and experiences in real time. FacialProof reveals when attention peaks, interest drops, or confusion appears — without surveys.

Use it to: optimize creatives, compare variants, and identify emotional friction.

Gaming & Virtual Worlds

Make experiences respond to the player.

Power emotion-aware avatars and NPCs that react to real facial expressions and mood shifts, creating deeper immersion and more believable interactions.

Use it to: drive NPC behavior, mirror expressions, and adapt gameplay dynamically.

Healthcare, Wellness & Education

Detect emotional state early — and act on it.

Monitor stress, engagement, and confusion in telehealth and learning environments without invasive sensors or self-reporting.

Use it to: track mood changes, detect disengagement, and adapt content or care in real time.

Passive vs. Active: The FacialProof Advantage

FeaturePassive Liveness (Invisible)Active Liveness (Challenge)
User EffortZero. The user just takes a selfie.High. User must blink or turn head.
Speed< 1 Second5 – 15 Seconds
Conversion95%+ Higher. No drop-offs.Lower due to user friction.
Best ForDaily logins & Retail OnboardingHigh-value transfers & KYC

Why FacialProof for Facial Expression Intelligence

Turn facial movement into measurable emotion, attention, and intent.
FacialProof delivers high-precision facial expression and sentiment analysis in real time, built for modern, human-aware applications.

What the API Actually Measures

FacialProof doesn’t return vague emotion labels.
It delivers structured behavioral signals you can analyze, score, and act on.

You receive:

  • Emotion probabilities (intensity + confidence, not just labels)
  • Micro-expression signals revealing subtle, involuntary reactions
  • Gaze direction & attention stability over time
  • Facial movement metrics (brow, eyes, mouth, jaw, cheeks)
  • Session-level emotional timelines for deeper analysis
Tourist taking photo of a building
Windows of a building in Nuremberg, Germany

Developer-First Expression API

One API. Real-Time Behavioral Insight.

Integrate facial emotion, expression, and gaze analysis using a single SDK.
Consistent logic across Python, JavaScript, PHP, Java, Android, and iOS, no fragmented workflows.

# Facial expression & emotion analysis
import facialproof

analysis = facialproof.analyze_frame(
    frame,
    include=["emotions", "gaze", "expressions"]
)

if analysis.attention.score < 0.4:
    adapt_experience()

FacialProof vs. Emotion Recognition APIs

When emotional accuracy matters, the differences are structural.
While cloud providers and legacy emotion APIs treat expression analysis as an add-on, FacialProof is built specifically for facial expression, emotion, and attention intelligence.

We focus on signal quality, granularity, and real-time usability, not generic vision tasks.

eature Comparison

FeatureFacialProofMicrosoft Azure / Google CloudAffectiva / Kairos / Hume AI
Primary FocusFacial expressions & emotionGeneral vision & identityEmotion research / multimodal
Landmark Density468-point 3D meshLow-density landmarksMedium density
Emotion OutputIntensity + confidence + timelinesStatic emotion labelsEmotion scores
Micro-ExpressionsSupportedNot supportedLimited
Gaze & AttentionBuilt-inLimited / separatePartial
Real-Time UseOptimized for live streamsImage-first pipelinesOften batch / research
Integration ModelSimple API, dev-firstCloud-heavy setupSDK-centric

1. More Precise Than Cloud Vision APIs

Emotion detection in Azure Face API and Google Cloud Vision is designed as a secondary feature of general image analysis.

FacialProof is different:

  • High-density facial landmark tracking
  • Continuous emotion change over time
  • Reliable results with head movement and natural expressions

If you need behavioral signal, not surface emotion tags, the gap is clear.

2. Built for Real-Time Emotion, Not Research Pipelines

Platforms like Affectiva, Kairos, and Hume AI pioneered emotion AI — but many are optimized for research, analytics, or multimodal experiments.

FacialProof is built for:

  • Live user interaction
  • UX, product, and engagement systems
  • Real-time emotion + attention feedback

No heavy SDKs. No research tooling overhead.

3. Expression Intelligence, Not Just Emotion Labels

Most emotion APIs answer “what emotion is this?”
FacialProof answers “what changed, how strongly, and for how long?”

That includes:

  • Expression intensity
  • Micro-movement detection
  • Gaze stability and attention loss
  • Session-level emotional timelines

This is facial expression intelligence, not generic emotion classification.


FAQs


What is a facial emotion and expression recognition API?

A facial emotion and expression recognition API analyzes facial movements to identify emotional states, expression intensity, and attention signals in real time. Instead of static labels, modern APIs like FacialProof measure how expressions change over time, capturing emotion strength, micro-expressions, and gaze behavior from video or images.


How is facial expression recognition different from basic emotion detection?


What makes a good emotion recognition API?


Can facial emotion recognition work in real-time applications?