Hreflang Validator for International SEO

Validate the hreflang setup of multilingual and multi-region sites, including the part most tools skip: do the alternates actually link back? Plain HTTP, no browser, no personal data.

What it checks

• Annotations from HTML <link rel="alternate" hreflang> and the HTTP Link header.
• Codes: invalid-code (e.g. en-UK, jp, en_US, numeric regions like es-419, wrong case of x-default).
• Set integrity: missing-self-reference, missing-x-default, conflicting-duplicate, duplicate, single-annotation, non-absolute-url, mixed-protocols, canonical-mismatch.
• Return links (optional, default on): fetches each alternate (up to maxAlternates) and reports missing-return-link, alternate-http-error, alternate-unreachable, alternate-redirects, alternate-canonical-mismatch.
• Sitemap-based hreflang (xhtml:link) is not covered in this version.

Input

Field	Default	Description
urls	required	Pages to validate (up to 2,000), one per site or template.
checkReturnLinks	true	Fetch alternates to verify reciprocity.
maxAlternates	25	Max alternates fetched per page (max 60).
respectRobots	true	Skip disallowed pages (not charged).
delayMs	400	Delay per host.
concurrency	3	Pages in parallel.

Output

{ "url": "https://example.com/en/", "status": 200, "hreflangCount": 4, "alternatesChecked": 3, "score": 88,
  "entries": [{ "hreflang": "de", "href": "https://example.com/de/", "source": "html" }],
  "issues": [{ "severity": "high", "id": "missing-return-link", "message": "Alternate does not link back to this page (return links are required).", "hreflang": "fr", "href": "https://example.com/fr/" }] }

Severity: high -12, medium -5, low -1 points from 100.

Safety and etiquette

Private/internal addresses blocked (SSRF guard on every redirect and at DNS level). robots.txt respected by default, max 2 parallel requests per host with a delay. The alternates fetched are the pages the site itself declares.

Pricing (pay per event)

apify-actor-start $0.005 per run (per GB), site-checked $0.005 per input URL fetched successfully (return-link checks of up to maxAlternates pages included; errors and robots-skipped pages not charged).

Develop

npm install && npm test; local run via storage/key_value_stores/default/INPUT.json + npm start; deploy apify push (private by default).