Hreflang is a tag to tell search engines the multiple versions of a page for different languages or regions you have for your website.
The tag will allow search engines to show the most appropriate URL to a user based on his location and language settings. This guide from Google will tell you everything you need to know about implementing hreflang attribute on your website.
If hreflang code is misconfigured, search engines may misinterpret it or ignore this attribute at best. Our Site Audit tool will be able to flag out these errors.
Hreflang annotation invalid
Pages with "hreflang" annotations (language or language & locales) that are not valid such as en-en and en-uk instead of en-gb
Language annotations in "hreflang" attributes must conform to ISO 639-1 format ; and locale annotations (optional) conform to ISO 3166-1 Alpha 2 format.
Self-reference hreflang annotation missing
Make sure each page on your website has a self-referencing "hreflang" annotation. For example, a Spanish version of your page must have rel="alternate" hreflang="es" annotation with a link to itself within "hreflang" annotations.
Page referenced for more than one language in hreflang
Review the "hreflang" annotations for the pages reported and make necessary updates so that one language version of a page is always referenced for one language only. You can, however, assign multiple locations with the same language in hreflang values to one URL, e.g. en-us, en-gb, etc.
More than one page for same language in hreflang
Make sure "hreflang" annotations are only declared once for a language (or language-locale) on a page.
Hreflang and HTML lang mismatch
Make sure the same language is declared in HTML lang attribute and in "hreflang" for the page.
Missing reciprocal hreflang (no return-tag)
To prevent this issue, make sure all the page versions translated or targeted to users in a certain region have the same set of "hreflang" annotations.
Hreflang to non-canonical
Make sure all the links in "hreflang" annotations on your pages point to the canonical page.
Hreflang to broken page
Review the links in "hreflang" annotations to make sure they point to live pages.
HTML Lang Attribute Missing
Make sure your pages have language (or language and country) code declared in the HTML lang attribute.
Hreflang defined but HTML lang missing
Do make sure your pages have language (or language and country) code declared in the HTML lang attribute