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ThinkTools

Lie Detector

A webcam lie detector game that scores each answer against your own baseline

  • Runs fully on-device
  • 10-second calibration
  • 8 facial cues
  • Desktop and browser versions
Buy now · $39.99See pricing

One-time payment · Delivered as soon as payment confirms · No added fees

  • Windows
  • macOS
  • Linux
  • Web

Lie Detector

Desktop Utilities

  • On-device face reading
  • Personal baseline
  • Eight weighted cues
  • Micro-expression detection
  • Live verdicts
Windows · macOS · Linux +1$39.99

Overview

About Lie Detector

Lie Detector turns a webcam into a party-game polygraph. It reads the face with an on-device landmark and expression engine and scores each answer for classic stress and discomfort cues: blink rate, gaze aversion, lip press, micro-expressions, brow tension, head motion, uneven smiles and eye widening.

First you calibrate for ten seconds by answering easy, truthful questions, so the engine learns your personal baseline for every cue. Then press Space to open a question, let the person answer, and press Space again to close it. A banner shows Truth, Inconclusive or Lie detected with the score and the strongest cues, and a side panel shows the live 0 to 100 score and each cue against baseline.

The desktop version is a Python app for macOS, Windows and Linux. The same engine and scoring also run in the browser through WebAssembly, with a live camera when you host it over HTTPS, or on uploaded clips. Video never leaves the device, and there is no cloud service involved.

Be clear about what it is: no facial-expression method can reliably tell truth from lies, and this one measures stress relative to a baseline. Use it for entertainment, demos, streams and experiments, never as evidence about a real person. Cue weights and verdict thresholds are plain settings you can tune.

Features

What it does

Reads 478 facial landmarks and 52 expressions on your device and scores answers for stress cues. Desktop and in-browser versions, made for fun and experiments.

  • On-device face reading

    478 landmarks, 52 blendshapes, head pose, and eye and mouth geometry, with no network access.

  • Personal baseline

    A 10-second calibration learns how the person looks when telling the truth.

  • Eight weighted cues

    Blink rate, gaze, lip press, micro-expressions, brows, head motion, smile symmetry and eye arousal.

  • Micro-expression detection

    Catches expression flashes of 40 to 500 ms that get masked.

  • Live verdicts

    Truth, Inconclusive or Lie detected for each question, with the score and the strongest cues.

  • Browser version

    The same engine in WebAssembly, for a live camera over HTTPS or uploaded clips.

  • Spoken verdicts

    Optional spoken results on macOS for a game-show feel.

  • Tunable scoring

    Adjust cue weights, overall gain and verdict thresholds to suit your room and camera.

Pricing

One price, everything included

Pay once in USD with crypto. Your download links and license key arrive by email as soon as the payment confirms.

Full source code

Desktop and in-browser versions, source included.

$39.99

One-time payment · USD · no fees added

Buy now

What you get

  • Complete source code (desktop and WebAssembly builds)
  • Calibration and scoring engine
  • All future updates at no extra cost
  • Email support

Every purchase includes

  • Instant delivery

    Download links and your license key by email as soon as payment confirms.

  • Free future updates

    Every future version at no extra cost, on your order page the day it ships.

  • Security reviewed

    Tested by our engineers and by AI-driven analysis before every release.

  • Pay with crypto

    The payment page shows the exact amount, the address and a QR code.

  • No added fees

    You pay exactly the listed price.

  • Support from real people

    Questions go to humans@thinktools.dev.

FAQ

Questions and answers

Can't find what you're looking for? See the store FAQ or write to humans@thinktools.dev.

Can it really detect lies?
No tool can reliably tell truth from lies by reading a face, and this one does not claim to. It measures stress and discomfort compared with the person's own baseline. It is made for fun, demos and experiments, not for decisions about real people.
What do I receive?
The complete source code for the desktop app and the WebAssembly browser version, the calibration and scoring engine, install and hosting guides, all updates and email support.
What do I need to run it?
For the desktop version, Python 3.10 or later and a webcam on macOS, Windows or Linux. The browser version needs HTTPS to use a live camera; without it, it analyzes uploaded clips.
Is any video uploaded?
No. Face analysis runs on your device in both versions, and no video or images are sent anywhere.
Can I change how it scores?
Yes. Cue weights, overall gain and the thresholds for each verdict are plain settings in the analysis module.
How do support and refunds work?
Email humans@thinktools.dev and a person will help. For refund terms, see Refunds.