If you run the same content in multiple languages, hreflang tells Google which version to show to which audience — and getting it wrong quietly kills your international traffic. Here's the plain-English version of how it works and how to check it.
Without hreflang, Google has to guess which of your language versions belongs in a given search result. A user in Tokyo searching in English might land on your Chinese page, or Google might index both versions as duplicates and rank neither. hreflang tags declare the relationship between versions so Google serves the right one.
Example for an English page and its Chinese counterpart:
<link rel="alternate" hreflang="en" href="https://example.com/about" />
<link rel="alternate" hreflang="zh" href="https://example.com/about-zh" />
<link rel="alternate" hreflang="x-default" href="https://example.com/about" />The most frequent errors are missing self-references, one-way links (page A points to B, but B doesn't point back), and wrong language codes such as zh-CN vs zh-Hans. All three produce the same symptom: your international pages stop showing up. The fixes are mechanical, but they're easy to get wrong across dozens of pages — which is why the hreflang generator exists.
Two checks cover most cases: use Search Console's International Targeting report, and use the generator to produce a consistent tag set for every page pair. Our free audit also flags missing or mismatched hreflang tags so you catch drift before it costs rankings.
If your site has an English page at /seo-guide and a Spanish version at /es/seo-guide, the tags on both pages should point to each other and to themselves. Each page declares a link with rel="alternate" and the right hreflang, plus an x-default pointing to the language you want as fallback. Missing the self-reference is the single most common error — every page must list itself. Our hreflang generator builds the full set so you cannot forget a link.
You do not need hreflang for a single-language site, or when your only variation is currency or minor wording rather than true language or regional differences. Adding tags that point to near-duplicate pages can confuse crawlers more than help. Use it when you genuinely serve different language or region experiences; otherwise spend the effort on translation quality and clear navigation instead.