If your site has English and Spanish versions of the same page, Google has to guess which one to show to whom. Hreflang is how you stop it guessing. It's a small tag in the page head that says, in effect, "this page has a twin, and here's where it lives".
What it looks like
Each page lists every language version of itself, including itself. The English page and the Spanish page carry the same set of links, so they point at each other. That reciprocity is the part people miss.
You can also add an x-default entry, which tells search engines which version to show when none of the languages match the visitor. On this site, x-default points to English.
Three mistakes that quietly break it
- One-way links. The English page points to the Spanish one, but the Spanish page doesn't point back. Google may ignore both.
- Pointing at the wrong URL. Hreflang should point to the final, canonical address of each page, not to a redirect or to a version with tracking parameters.
- Translating the homepage only. If the Spanish "Services" page is just a link back to English, don't pretend it's a twin. Only pair pages that really exist in both languages.
How to check yours
Search Console no longer has a dedicated hreflang report, so the practical check is to open a page, view the source, and make sure each alternate URL loads and points back. A crawler can do the same across the whole site.
It's not glamorous work, but on a bilingual site it's often the difference between your Spanish pages being found and being invisible.
How this note was made: drafted with AI assistance and edited by Mogens, who reviews every note before it goes live. How I use AI.