Sample the real content
Cross-check URL, HTML, hreflang, and the language detected in the visible text.
Page-by-page language verification
Find the pages that speak the wrong language.
Crawl your multilingual website, compare each page’s declared language with its real content, and get an actionable report.
No account. No card.
Full report with JSON, CSV, and PDF exports.
See the deliverable
A report your team can act on.
Explore a labelled example with expected and detected languages, per-page verdicts, and downloadable exports.
EXAMPLE DATA
Click or tap a page to reveal the verdict.
Reproducible benchmark
Proof, not promises.
We tested the detection engine on 36 languages of real marketing copy. The method and raw results are public.
80.6%top-1 accuracy on full pages
3,701short-string samples tested
0.39 msaverage detection call
36languages in the benchmark
Read the methodology and raw benchmark · Compare detection approaches
Method
Three reads. One verdict per page.
Remove the template
Read the full body without navigation, cookie banners, or footer text hiding untranslated content.
Arbitrate doubtful pages
Escalate mixed or uncertain signals, then report one clear status per page.
Pricing
Scan once, or watch every deployment.
Start free. Paid crawls and subscriptions require an account; card payment is handled by Stripe.
Pay per page
Small site
$4 / crawl
200 pages
Medium site
$8.50 / crawl
500 pages
Large site
$27 / crawl
2,000 pages
Account required for paid crawls. Provided URLs cost less than spider crawling.
Recurring monitoring
Starter
$9 / month
- 1 site
- Weekly scan
- Crawl-to-crawl comparison
- PDF report
Pro
$29 / month
- 5 sites
- Weekly scan
- Slack, Teams, and webhook alerts
- JSON / CSV / PDF exports
Agency
$99 / month
- 25 sites
- Daily scan
- White-label
- SSO + priority support
Account required for subscriptions.
FAQ
Frequently asked questions
What does Lingua Detective actually check?
It crawls your site and verifies that each page served under a given language is really written in that language — no leftover source language, no mixed content. Every page gets a verdict: Conforming, Non-conforming, Uncertain, Error, or Undetermined.
How many languages can it detect?
Detection covers more than 180 ISO 639-3 languages; the public benchmark evaluates 36 languages, and the interface is localized into 36 languages. The text of your pages is never sent to a third-party AI service for detection.
Do I need an account or a subscription?
Not for the free scan: the first 10 pages need no card or account. Paid crawls and subscriptions require an account and card checkout.
What does a large site cost?
A spider crawl costs $4 for 200 pages, $8.50 for 500, or $27 for 2,000. Providing URLs costs less: $3, $6, or $17 respectively. Recurring monitoring starts at $9 / month.
Does it work on JavaScript-heavy sites?
Real Chromium rendering is available to subscribers. The free scan uses HTTP crawling without JavaScript rendering, so a JavaScript-dependent site can produce a different result from a paid crawl.
Can an AI agent use the API directly?
Yes. The API speaks x402 (HTTP 402 micropayments in USDC on Solana) and ships an MCP server for agent frameworks: the agent pays per call, without an API key or an account.