@probecheck/probe-engine

Browser-based device diagnostics engine — test webcam, microphone, keyboard, screen, mouse, speakers, and more. Zero dependencies, privacy-first.

Part of ProbeCheck.

Features

| Module | What it tests | |--------|---------------| | webcam | Resolution, FPS, video quality, device enumeration | | microphone | Volume, sample rate, noise floor, input quality | | keyboard | All keys, N-key rollover, ghosting, response time | | screen | Resolution, DPR, HDR, dead pixel detection | | mouse | Buttons, scroll, polling rate estimation | | speaker | Audio output availability, test tone generation | | gamepad | Buttons, axes, haptic feedback | | touch | Touch events, multi-touch, gesture support | | webgl | GPU vendor, renderer, capabilities | | network | Download speed, jitter, packet loss, latency | | latency | Input latency measurement | | polling | Mouse polling rate estimation | | audio-frequency | Audio frequency sweep, tone generation |

Install

npm install @probecheck/probe-engine

Usage

import { webcamProbe, microphoneProbe, keyboardProbe } from "@probecheck/probe-engine";

// Run a webcam test
const result = await webcamProbe.run();
console.log(result.status); // "pass" | "fail" | "warning" | "unsupported"
console.log(result.details); // { width, height, fps, devices, ... }

// Run a microphone test
const micResult = await microphoneProbe.run();
console.log(micResult.details); // { sampleRate, volume, noiseFloor, ... }

// Check if a feature is supported before testing
if (keyboardProbe.isSupported()) {
  const kbResult = await keyboardProbe.run();
}

API

Every probe module follows the ProbeModule interface:

interface ProbeModule {
  type: string;
  isSupported: () => boolean;
  run: (options?: ProbeOptions) => Promise<ProbeResult>;
  stop: () => void;
}

interface ProbeResult {
  type: string;
  status: "pass" | "fail" | "warning" | "unsupported";
  summary: string;
  details: Record<string, unknown>;
  hints?: ProbeHint[];
  timestamp: number;
  duration: number;
  precision: "high" | "medium" | "low" | "estimate";
}

Options

interface ProbeOptions {
  timeout?: number;      // Timeout in ms (default: 10000)
  onProgress?: (data: unknown) => void; // Progress callback
}

Built-in Scenarios

import { scenarios, getProbeModule } from "@probecheck/probe-engine";

// Get probe types for a scenario
const videoCallProbes = scenarios["video-call"];
// → ["webcam", "microphone", "speaker", "network"]

// Run all probes in a scenario
for (const type of videoCallProbes) {
  const probe = getProbeModule(type);
  if (probe?.isSupported()) {
    const result = await probe.run();
    console.log(`${type}: ${result.status}`);
  }
}

Available scenarios: video-call, laptop, streaming, gaming, full, audio.

Browser Support

Requires modern browser APIs:

• navigator.mediaDevices.getUserMedia (webcam, microphone)
• KeyboardEvent / Keyboard API (keyboard)
• Screen API (screen)
• AudioContext (speaker, audio-frequency)
• Gamepad API (gamepad)
• WebGL API (webgl)
• NetworkInformation API (network)

Works in Chrome 90+, Edge 90+, Firefox 90+, Safari 15+. Older browsers may have partial support.

Privacy

All tests run entirely in the browser. No data is sent to any server. This package has zero telemetry.

License

MIT