Hreflang Checker (Free)

Check hreflang the way Google describes it: valid language and region codes, every page listing itself, return links between every pair, one URL per code, x-default, and alternates that redirect, 404, are noindex or canonicalize somewhere else. Works on a live site, an XML sitemap, or a static build folder before you deploy.

python3 -m hrefcheck https://example.com/ --max-pages 50                 # live: reads <head> tags and HTTP Link headers, follows alternates
python3 -m hrefcheck --sitemap https://example.com/sitemap.xml           # xhtml:link annotations in a sitemap (file or URL)
python3 -m hrefcheck --dir dist --base https://example.com/ --csv issues.csv   # a local build, mapped to its public URLs

Exit code 1 if there's anything high severity, so it can run in CI.

• Codes: ISO 639-1 language first, optional ISO 15924 script (zh-Hant) and ISO 3166-1 alpha-2 region; catches en_US, region alone (gb), en-UK (use en-GB), EU/UN, es-419, three-letter languages, unknown codes.
• Sets: fully-qualified URLs only, each page lists itself (and with the exact URL form), no code pointing to two URLs, x-default present, a language catch-all when you have several regions (en-GB + en-US but no en).
• Pairs: every alternate links back, and calls this page by the same code; differences in trailing slash or www are pointed out.
• Targets (live and --dir): alternates that redirect, return 4xx/5xx, are noindex (meta robots or X-Robots-Tag), or have a rel=canonical pointing elsewhere; hreflang tags placed outside <head>; HTML tags and Link header that disagree.
• Sitemaps: the xhtml namespace, valid XML, alternates with no <url> entry of their own.

Rules follow Google Search Central's "Tell Google about localized versions of your page" (checked Nov 9, 2026). Run ./demo.sh for the examples and ./run_tests.sh for the tests. Python 3.9+, no dependencies.

• Private and local addresses are blocked by default; set HREFLANG_ALLOW_PRIVATE=1 to check a staging server on your network.
• --max-pages (default 50) caps a crawl; the report says how many linked pages weren't checked.
• Sites that block bots may return different pages to this checker than to Google.