What is hreflang used for?

Hreflang tells Google that several URLs are language or regional versions of the same page, so it can show each searcher the most appropriate one, such as the UK page in Britain and the German page to German speakers. It doesn't detect a page's language and doesn't guarantee every version gets indexed.

Do hreflang tags need return links?

Yes. If page A lists page B as an alternate but page B doesn't list page A back, Google ignores that pair. Every version should carry the same block, listing itself and every other version with identical absolute URLs. Missing return links are the most common reason hreflang silently does nothing.

Is it en-uk or en-gb in hreflang?

Use en-gb. Hreflang region codes follow ISO 3166-1 alpha-2, where the United Kingdom is GB. UK is a reserved code, and Google's documentation says it ignores reserved region codes such as UK, EU and UN, so en-uk gives the page no UK targeting.

How do I check if hreflang is working?

Google retired Search Console's International Targeting report in 2022, so check manually. Confirm each version has the full block in its head, every pair links both ways, and each target URL returns 200 with no redirect, noindex or conflicting canonical. An hreflang checker or site crawler speeds this up.

Hreflang Tags: Setup Guide & the Return-Link Mistake

Q: What is x-default in hreflang?

x-default is a reserved hreflang value for visitors whose language settings match none of your listed versions. Google says it was designed for language-selector pages and works best with them, but it can point at any page, such as your main-market version. It is optional and needs no language code.

The short answer

Hreflang is an attribute on a <link rel="alternate"> tag that tells Google which URL is the version of a page for a given language or region. Every version carries the same block: one tag per version, including itself, plus an optional x-default fallback. Values are an ISO 639-1 language code (de), optionally followed by an ISO 3166-1 alpha-2 region (en-gb), and every URL must be absolute. The rule that breaks most setups is reciprocity: if page A lists page B and B doesn't list A back, Google ignores the pair.

What hreflang is used for

Hreflang doesn't detect language — Google does that with its own algorithms and doesn't use hreflang or the HTML lang attribute for it. Hreflang tells Google that several URLs are localized versions of the same content, so it can show a London searcher the UK page and a German speaker the German one. It matters most for same-language regional pages, such as US and UK versions that differ only in currency and spelling and otherwise look like duplicate content. It isn't a guarantee, though: Google's John Mueller has said hreflang doesn't guarantee indexing.

The syntax, and where it goes

A pricing page with US English, UK English and German versions puts this identical block in the <head> of all three:

<!-- The same block goes in the <head> of all three versions -->
<link rel="alternate" hreflang="en-us"
      href="https://example.com/en-us/pricing/" />
<link rel="alternate" hreflang="en-gb"
      href="https://example.com/en-gb/pricing/" />
<link rel="alternate" hreflang="de"
      href="https://example.com/de/pricing/" />
<link rel="alternate" hreflang="x-default"
      href="https://example.com/en-us/pricing/" />

Google's rules: the tags must sit inside a well-formed <head>, each href must be fully qualified (https://example.com/de/pricing/, never /de/pricing/), and hreflang shouldn't share a tag with attributes such as media. Alternates can live on other domains. The Hreflang Tag Generator builds this block, or the sitemap version, from rows of language, region and URL.

The return-link mistake everyone makes

Google's documentation is blunt: if two pages don't both point to each other, the tags are ignored. That stops another site from declaring itself the French version of your page. So when the German page lists the UK page but the UK page doesn't list the German one, Google drops that pair with no visible error. Missing return links top Google's own list of common hreflang mistakes, and they usually creep in one of three ways:

A new language is added on one side only. The new Spanish page gets the full block, but the English and German templates are never updated to list it.
The return link points at a slightly different URL — http:// instead of https://, www versus the bare domain, a missing trailing slash. That's a link to a different URL, not back to the page.
Tags only exist on the home page. Hreflang is page-level: every localized page needs its own block listing its own equivalents.

The consolation: Google still uses the pairs that do point to each other, so one missing return link breaks that pair, not the whole set.

Language and region codes that fail silently

Region on its own. The first code is always read as a language, so be means Belarusian, not Belgium. Use nl-be or fr-be.
en-uk instead of en-gb. The UK's ISO code is GB. UK is a reserved code, and Google says it ignores that part of the annotation.
es-la or es-419 for Latin America. LA is Laos, and Google explicitly lists es-419 as unsupported. Use country codes such as es-mx, or plain es.
Country codes as languages. Japanese is ja, not jp; uk alone is Ukrainian.
Script variants. zh-tw implies Traditional Chinese, or state the script directly with zh-Hant or zh-Hans, optionally plus a region.

What x-default is for

x-default catches visitors whose language settings match none of your versions — a Japanese speaker on a site with only English and German pages. Google says it was designed for language-selector pages and works best with them, but it can point at any page; the example above falls back to the US version. It's optional and belongs in the block on every version like any other entry.

Paste a URL into CheckSEO's Hreflang Validator to list every hreflang tag on the page and flag a missing self-reference, one code pointing at two URLs, malformed values like en_US, and a missing x-default. No signup.

Validate a page's hreflang tags

Every hreflang URL must be canonical, indexable and live

Point only at the final HTTPS URL that returns 200. A redirecting URL has no page of its own to carry a return tag, and Google's canonicalization guide says not to put HTTP versions in hreflang. Skip noindex pages, which can't appear in results, and URLs blocked in robots.txt, whose tags Google can't crawl. Make each target its own canonical, too: Mueller has written that if the canonical URL isn't part of the hreflang pairs, the markup is ignored. Never canonicalize the German page to the English one.

Three ways to implement hreflang

Google treats HTML tags, an XML sitemap and HTTP headers as equivalent. Mixing them is allowed but brings no benefit in Search and is harder to manage — two sources that disagree break pairs. Pick one.

HTML head, shown above, is the easiest to inspect, but adding a language means editing every existing version. XML sitemap keeps markup out of templates, which suits large sites. Declare the xhtml namespace on <urlset>, give each version its own <url>, and repeat the full set of xhtml:link children, self included, under each. The usual rules in our sitemap validator guide still apply.

<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"
        xmlns:xhtml="http://www.w3.org/1999/xhtml">
  <url>
    <loc>https://example.com/en-us/pricing/</loc>
    <xhtml:link rel="alternate" hreflang="en-us"
                href="https://example.com/en-us/pricing/" />
    <xhtml:link rel="alternate" hreflang="en-gb"
                href="https://example.com/en-gb/pricing/" />
    <xhtml:link rel="alternate" hreflang="de"
                href="https://example.com/de/pricing/" />
    <xhtml:link rel="alternate" hreflang="x-default"
                href="https://example.com/en-us/pricing/" />
  </url>
  <!-- Repeat a <url> entry for /en-gb/pricing/ and /de/pricing/,
       each with the same four xhtml:link lines -->
</urlset>

HTTP Link header is for files without an HTML head, mainly PDFs. Each version returns the same header, including the requested file. It's wrapped here for readability.

HTTP/1.1 200 OK
Content-Type: application/pdf
Link: <https://example.com/en-us/guide.pdf>; rel="alternate"; hreflang="en-us",
      <https://example.com/en-gb/guide.pdf>; rel="alternate"; hreflang="en-gb",
      <https://example.com/de/guide.pdf>; rel="alternate"; hreflang="de",
      <https://example.com/en-us/guide.pdf>; rel="alternate"; hreflang="x-default"

How to check hreflang is working

Search Console's International Targeting report used to flag hreflang errors, but Google retired it in September 2022. Checking is now on you:

Check the head of every version

Confirm the block sits inside the <head> of each version and is identical across them. An invalid element earlier in the head can close it and push the tags into the body.

Confirm every pair points both ways

Each block must list itself and every other version using exactly the same URLs. On large sites, a crawler such as Screaming Frog's SEO Spider reports missing return links in bulk.

Test each target URL

Every href should return 200 with no redirect, no noindex and a self-referencing canonical. Run doubtful ones through the Redirect Chain Checker and the Canonical URL Analyzer.

Watch which URL Google picks

URL Inspection in Search Console shows the Google-selected canonical. If a regional page reports another version as canonical, Google has folded them together.

Does Bing use hreflang?

Only weakly. In 2020 Microsoft's Fabrice Canel called hreflang "a far weaker signal than content-language" at Bing, whose webmaster guidance has long favoured the content-language meta tag. If Bing matters to you, add one per version: <meta http-equiv="content-language" content="en-gb">.

Check your hreflang tags

CheckSEO's Hreflang Validator fetches a live URL, lists every hreflang entry with the absolute URL it resolves to, and checks for a self-reference, duplicate codes, malformed values and a missing x-default. It checks one page at a time without following the alternates, so run each language version through it and compare the lists — a URL missing from one list is a broken return link.

Hreflang Tags: The Complete Setup Guide (With the Return-Link Mistake Everyone Makes)