Technical2 min readMarch 10, 2026

Active vs. Passive Liveness Detection: Which Should You Use?

Compare active and passive liveness detection approaches — understand the trade-offs between security, user experience, and implementation complexity.

Two Approaches to Liveness

Both active and passive liveness detection solve the same problem: ensuring a face belongs to a real, live person. But they take very different approaches.

Passive Liveness Detection

How it works: Analyzes a single image using AI to detect signs of spoofing — texture analysis, reflection patterns, depth cues, and other signals that distinguish real skin from screens and paper.

Pros:

• Zero friction — user just takes a selfie

• Fast — single API call

• Works on any device with a camera

Cons:

• Slightly lower security than active liveness

• Cannot detect very sophisticated 3D masks

Learn more in our deep dive on passive liveness.

Active Liveness Detection

How it works: Generates a random set of instructions (look up, look left, etc.) and asks the user to perform them on video. The system verifies the movements were performed in the correct sequence.

Pros:

• Higher security — very difficult to spoof

• Proves the person is present and responding in real-time

• Combined with passive liveness on each frame

Cons:

• Requires more user interaction

• Needs video recording capability

• Slightly longer verification time

bash

Step 1: Request a challenge

curl -X POST "https://faceapi.arsa.technology/api/v1/face_liveness_active/request?difficulty=medium" \

-H "x-key-secret: YOUR_API_KEY"

Response: {"instructions": ["up", "left"], "job_uuid": "..."}

Step 2: Record video of user performing movements, then submit

curl -X POST "https://faceapi.arsa.technology/api/v1/face_liveness_active/submit?job_uuid=UUID" \

-H "x-key-secret: YOUR_API_KEY" \

-F "video=@recording.mp4"

Which Should You Choose?

| Scenario | Recommended |

|----------|------------|

| Quick onboarding, low risk | Passive only |

| KYC/banking, medium risk | Passive + selfie-to-ID comparison |

| High-security, regulated | Active + passive combined |

| Exam proctoring | Active (continuous) |

ARSA Offers Both

ARSA Face Recognition API includes both passive and active liveness detection. Start your free trial or view the documentation.

Ready to get started?

Try ARSA Face Recognition API free with 100 API calls/month.

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