What Hreflang Does and Why It Is So Easy to Break
Hreflang tells Google which version of a page to show to searchers in different language and regional markets. Without it, a site serving Spanish, French, and English content risks showing the wrong language to the wrong audience. Generate the correct tags for every variant with our Hreflang Tag Builder.
The Three Most Common Hreflang Errors
- Non-reciprocal tags: Every page in the alternate set must reference every other page in the set, including itself. If your English page references your Spanish page but your Spanish page does not reference your English page back, Google ignores the entire set for the non-reciprocating pages.
- Wrong ISO codes: Language codes must follow BCP 47 format —
en-US,es-MX,fr-CA. Using underscores, uppercase, or invented region codes silently fails. - Missing x-default: The
hreflang="x-default"tag specifies which URL to show to users who do not match any explicitly listed combination. Omitting it means non-targeted users see an arbitrarily chosen variant.
Delivery Options: Link Tag vs. HTTP Header vs. Sitemap
There are three ways to deliver hreflang signals: HTML link tags in the page head, HTTP response headers (for non-HTML content like PDFs), and sitemap XML entries. The sitemap method is easiest to manage at scale, but requires flawless sitemap maintenance. For most sites, the HTML tag method is safest because it is most visible during audits.