OpenTechCheck

See what websites are built with. Open-source technology fingerprinting for the web.

Detects the technologies behind a website — frameworks, CMS, analytics, CDN, and more — with confidence scores and the evidence for every detection.

Install the Chrome extension · opentechcheck.com

Packages

Package	Purpose
@opentechcheck/core	Pure detection engine: detect(bundle, fingerprints)
@opentechcheck/fingerprints	Community fingerprint registry (YAML → compiled JSON)
@opentechcheck/collect-http	Fetch-based signal collector

Quick start

Run bun install && bun run compile first to build the fingerprint registry that the example imports.

import { detect } from '@opentechcheck/core'
import { collect } from '@opentechcheck/collect-http'
import fingerprints from '@opentechcheck/fingerprints'

const result = await collect('https://example.com')
if (result.ok) console.log(detect(result.bundle, fingerprints))

Development

bun install
bun test
bun run compile   # validate + build the fingerprint registry

Browser extension

Local-only technology detection for the current page (Chrome ≥ 121, Firefox ≥ 128).

Install from the Chrome Web Store, or build from source:

bun run compile          # refresh the fingerprint registry
cd packages/extension
bun run build            # emits dist/chrome and dist/firefox

Load dist/chrome via chrome://extensions → "Load unpacked" (enable Developer mode), or dist/firefox via about:debugging → "Load Temporary Add-on". Detection runs entirely in your browser; no request ever leaves it.

Contributing

Add a technology in one YAML file plus one fixture — see CONTRIBUTING.md.

License

Apache-2.0