Domain Enrichment API

Endpoint: GET /api/website/html

Domain enrichment turns a website or email domain into a company record. The endpoint downloads a public web page and, with extract=true, returns the company candidates found in it: registration numbers (KVK, Companies House, Handelsregister), VAT numbers, JSON-LD organisation data, copyright and legal-suffix names. Resolve a candidate with /api/company/search and you have the registered legal entity behind the site, with firmographics, CEO, corporate group and contact data from 350M+ companies in official registers. This is the domain enrichment step that powers Find the Company Behind Any Website and the Chrome extension.

Typical uses:

Inbound lead enrichment: a signup from info@acme.nl becomes Acme B.V. with size, industry, city and CEO before sales follows up.
CRM enrichment by domain: enrich every company record that only has a website field, in bulk.
Prospect and account lists: turn a directory, a competitor's customer logos or a list of domains into a target list with registry-verified firmographics.
Registry-backed alternative to Clearbit-style enrichment: the same domain-in, company-out call, sourced from official registers instead of scraped profiles.
Fallback for the website filter: when /api/company/search?website= returns nothing, the footer or imprint usually still names the operator.
Your own parsing: the raw HTML is returned as well, so you can run any extraction you like without hosting a fetcher.

Request

GET

/api/website/html

curl -G "https://app.companydata.com/api/website/html" \
  -H "x-api-key: YOUR_API_KEY" \
  --data-urlencode "url=coolblue.nl" \
  --data-urlencode "extract=true"

Query parameters

Parameter	Required	Description
`url`	yes	The page to download. A bare domain (`coolblue.nl`), a host with path (`www.example.com/imprint`) or a full `http(s)://` URL. Bare domains default to `https://`.
`extract`	no	`true` to include the `candidates` array with company signals found in the page. Default `false`.
`maxBytes`	no	Cap on the downloaded body in bytes. Default `2000000` (2 MB), minimum `10000`, maximum `5000000`. Larger pages are cut off and flagged with `truncated: true`.

Redirects are followed (up to 5 hops) and finalUrl tells you where the page ended up. The body is decoded using the charset declared by the server or the page; charset reports which one was used.

Response

{
  "requestedUrl": "https://coolblue.nl/",
  "finalUrl": "https://www.coolblue.nl/",
  "statusCode": 200,
  "contentType": "text/html; charset=utf-8",
  "charset": "utf-8",
  "html": "<!DOCTYPE html><html lang=\"nl\">...",
  "bytes": 412873,
  "truncated": false,
  "redirects": ["https://www.coolblue.nl/"],
  "fetchedAt": "2026-09-07T10:12:31.204Z",
  "candidates": [
    { "source": "jsonld", "name": "Coolblue B.V.", "countryHint": "NL", "city": "Rotterdam" },
    { "source": "identifier", "nationalId": "24330083", "countryHint": "NL" },
    { "source": "identifier", "nationalId": "NL812688747B01", "countryHint": "NL" },
    { "source": "copyright", "name": "Coolblue", "countryHint": "NL" }
  ]
}

Response fields

requestedUrl: the normalised URL that was fetched first.
finalUrl: the URL after redirects. Use its hostname for the website filter or as the domain to cache on.
statusCode: HTTP status of the final response. A 404 or 503 page is still returned so you can inspect it.
contentType and charset: as declared by the server and used for decoding.
html: the page body as text, up to maxBytes.
bytes and truncated: how much was downloaded and whether the cap was hit.
redirects: every redirect target that was followed, in order.
candidates (only with extract=true): company signals in order of trust, deduplicated, at most 12.

Candidate sources

`source`	What it is	Reliability
`jsonld`	`Organization` / `LocalBusiness` from schema.org JSON-LD: `legalName` or `name`, `vatID` or `taxID`, address	High when present
`identifier`	Registration or VAT number from the footer or imprint: KVK (NL), Company No. (GB), HRA/HRB (DE), EU VAT numbers	Very high: search it with `nationalId=`
`copyright`	The name after the copyright line	Medium: often a trade name
`legal-suffix`	Names ending in B.V., GmbH, Ltd, Inc., S.A. and similar found in the footer	Medium to high
`og`	`og:site_name` or `application-name` meta tag	Low: usually a brand

Each candidate carries a countryHint (from the identifier prefix, the JSON-LD address, or the country-code top-level domain) that you should pass as countryCode to narrow the search.

From website to lead

Call /api/website/html?url=<domain>&extract=true.
If a candidate has a nationalId, search it directly: /api/company/search?nationalId=<id>&countryCode=<countryHint>. A hit here is near-certain.
Otherwise search the best name candidate: /api/company/search?search=<name>&countryCode=<countryHint>&statusCode=0,1, and compare the returned Company Name and Trade Name with the candidate.
If nothing matches, fall back to the registry's own website field: /api/company/search?website=<hostname>.
Export the match with /api/company/export?ID=<id> for the full lead record: phone, email, employees, revenue, industry codes, executives and headquarters fields.

Company websites list the operating company, not necessarily the ultimate owner. Once you have a match, the export record's Global Headquarter ID Number gives you the group parent; see Corporate Structure.

Errors

Status	`code`	Meaning
`400`	`invalid_url`	`url` is missing, not http(s), contains credentials, or is not a public hostname.
`401`		Missing or invalid API key.
`403`	`blocked_host`	The host is an IP literal, an internal name, or resolves to a private or reserved address. Only public websites can be fetched.
`415`	`not_html`	The URL returned a non-HTML document (an image, a PDF, a JSON API).
`429`		Monthly quota exceeded for this key.
`502`	`unreachable`, `too_many_redirects`	The site could not be reached, did not resolve, or redirected more than 5 times.
`504`	`timeout`	The site did not respond within 10 seconds.

Limits and quota

One call counts as one request against your monthly quota, whatever the page size.
Pages are fetched with a CompanyDataBot user agent from our servers; sites that block bots may return a challenge page instead of their content (check statusCode and the html).
Only http and https URLs on public hosts are fetched. Private networks, cloud metadata addresses and localhost are always refused.
Downloaded HTML is not stored; each call fetches the page live.