URL to test
Hreflang tags detected
| Lang | URL | Source | ISO code | Reciprocity |
|---|
Check the compliance of your hreflang tags, ISO codes, reciprocity between language versions, x-default, self-reference. The #1 cause of indexing problems on multilingual sites.
| Lang | URL | Source | ISO code | Reciprocity |
|---|
Four things. First, the list of <link rel="alternate" hreflang> tags detected in the HTML <head> and in the HTTP Link header. Second, ISO code validity per BCP 47 (language plus optional region). Third, reciprocity, every alternate page must point back to the source. Fourth, presence of x-default and self-reference (the page must declare itself in its own hreflangs).
BCP 47 format: fr, en (language only), or fr-FR, en-US (language plus ISO 3166-1 alpha-2 region). x-default is valid and designates the default version (typically the English home). Common mistakes: fr_FR (underscore instead of hyphen), fr-fra (3 letters for the region instead of 2), fr-fr (region in lowercase). Google is tolerant but the tool flags non-conformities.
Without reciprocity (each alternate must point back to the source), Google ignores the entire hreflang cluster. Concrete consequence: Google serves the wrong language version in SERPs, or worse, considers your multilingual pages as duplicate content. This is the #1 mistake on international sites: tags are placed once on the FR version but the EN/DE versions do not have the mirror table.
Any one of the three methods is enough. (1) HTML <link rel="alternate"> tags in <head>, (2) HTTP Link header, (3) xhtml:link annotations in sitemap.xml. The HTML method is the most common because the most auditable. The sitemap is useful for sites with many languages (saves repeated HTML on every page). This tool tests methods 1 and 2, sitemap support will arrive in a future version.
Nautilinks has a network of French and German media for contextual per-language links, with no intermediary.