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

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))

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

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 apps/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. Optional reports open the website’s prefilled form; no report is sent until you submit it.

An optional Automatically report undetected websites setting is off by default. When enabled, completed empty scans can submit only the website domain. Private browsing and local-network sites are excluded; submissions are deduplicated and capped. Detection rescans after loading, relevant page changes, and opening the popup.

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

Apache-2.0