Knowledge base v2.13.0 · Community edition · data through 2 October 2026
Topic · International and multilingual sites
Google extracts hreflang while processing a page's HTML to learn its other-language equivalents, called it useful in ranking, and said it tries to use hreflang alternates when it clusters same-language pages for different countries (German pages for Germany, Austria and Switzerland) so it can show the right country version. Google's internationalisation talk listed the common mistakes: missing return links (Google ignores one-way annotations, since an alternate URL can be on any domain and any site could otherwise claim to be another site's language version), missing self-references, several methods at once with conflicting values, and invalid codes such as se, dk or cz instead of sv, da or cs, UK instead of GB, EU, city codes or a region code with no language. Google's hreflang guide agrees and adds detail: the HTML head, HTTP header and sitemap methods are equivalent and combining them brings no benefit (so using only one is the talk's advice against conflicts, not a documented rule), alternate URLs must be fully qualified and may be on other domains, and hreflang is recommended even for small regional variations or when only the template is translated. Google does not use hreflang to determine a page's language, and its canonical documentation says the canonical of an hreflang page should be in the same language and that URLs in hreflang clusters are preferred as canonicals; a community speaker called canonical links between language versions a misuse that would leave only one language ranking. A community speaker cited a third-party study (reported in 2017, auditing 20,000 multilingual sites) that found at least one hreflang error on 75% of them, and stressed that hreflang only routes users to the right version: it does not make a site trusted in a new country, and understanding each market is the harder part. Day 3 added the query side: a brand-only query does not reveal which language the user wants, so Google sometimes shows the wrong language version for brand searches, falling back on location and browser settings, and it applies language and country already at retrieval, before ranking. Author’s view: that makes hreflang and a visible language switcher the safeguard for brand searches. Google's internationalisation talk added that incorrect language and region codes are a mistake it finds very often, with the same wrong codes coming up again and again, especially in Europe, because site owners assume the codes are easy; a second recording of the deduplication talk confirmed that its short advice for same-language, different-country pages was simply to use hreflang.
Things in this topic 7
Counts are claims that name the thing. All things
What to do
Google extracts hreflang annotations, through which site owners specify the language variants of their content, to know whether a page has an equivalent with similar content in another language.
Speaker Cherry PrommawinIn Day 2, 10:25 · How is HTML interpretedEvidence slide photo, transcript
Used byglossary term hreflang
Alternate names also serve localization: if Google knows that country versions such as you.de and you.at are equivalent, it can pick the right version to show using hreflang.
Speaker John MuellerIn Day 2, 11:55 · Handling web duplicationEvidence slide photo
Same-language content for different countries is tricky for Google's deduplication, notably German pages for Germany, Austria and Switzerland, and possibly Spanish-language variants.
Speaker John MuellerIn Day 2, 11:55 · Handling web duplicationEvidence slide photo, transcript
Used byrequirement DEV-INT-08
When localized pages are clustered, Google tries to use hreflang alternates; the speaker's short version of the advice was to use hreflang, which he called really helpful for same-language, different-country content.
“We try to use hreflang alternates.”
Wording checked against the slide or recording
Speaker John MuellerIn Day 2, 11:55 · Handling web duplicationEvidence slide photo, transcript
Used byrequirement DEV-INT-08
Language versions can also be language-plus-region variants: Google's example site had a generic English page (en), a UK English page (en-gb) and a Spanish page (es), each on its own URL.
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence slide photo, transcript
Used byrequirement DEV-INT-01
Google's hreflang example lists every language version in the page's HTML head as a link element with rel=alternate, the version's full URL and its hreflang code (en, en-gb, es), including the page's own URL.
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence slide photo, transcript
Used byrequirement DEV-INT-03glossary term hreflang
Missing return links are a common hreflang mistake: if page X names page Y as a language version, page Y must link back to page X.
“If page X links to page Y, page Y must link back to page X.”
Wording checked against the slide or recording
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence slide photo, transcript
Used byrequirement DEV-INT-03glossary term hreflang return link
hreflang language codes must be ISO 639-1 codes: Google's list of common mistakes marked se, dk and cz (the country codes of Sweden, Denmark and Czechia) as wrong and sv, da and cs (Swedish, Danish, Czech) as right.
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence slide photo, transcript
Used byrequirement DEV-INT-04
hreflang region codes must be ISO 3166-1 Alpha-2 country codes; frequent mistakes are UK instead of GB for the United Kingdom, SW instead of CH for Switzerland and GE instead of DE for Germany.
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence slide photo, transcript
Used byrequirement DEV-INT-04
EU is not a valid hreflang region code: sites use it hoping to target the European Union, but hreflang targeting works only by country.
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence slide photo, transcript
Used byrequirement DEV-INT-04
Google also flagged LA used as a region code for Los Angeles (a city, not a country) and SA used for South Africa as wrong hreflang region codes.
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence slide photo, transcript
Used byrequirement DEV-INT-04
A region code cannot be used on its own in hreflang: en and en-GB are valid values, but GB alone is not, because the value must name a language.
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence slide photo, transcript
Used byrequirement DEV-INT-04
The speaker said that knowing a page's other-language versions from hreflang is useful in ranking.
Speaker Cherry PrommawinIn Day 2, 10:25 · How is HTML interpretedEvidence transcript
Canonical links between different language versions of a page are a misuse: if a search engine accepted such a canonical group, only one language version would rank.
Speaker Tobias SchwarzIn Day 2, 12:05 · Lightning session E: Managing Duplicates and Site MovesEvidence transcript
Used byrequirement DEV-CAN-06
Language versions of a page should be connected with hreflang annotations instead of canonical links.
Speaker Tobias SchwarzIn Day 2, 12:05 · Lightning session E: Managing Duplicates and Site MovesEvidence transcript
Used byrequirement DEV-CAN-06
Google may find a site's different language versions on its own, without the site owner doing anything, but owners can take steps to make this easier for Google.
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence transcript
Each language version should have its own URL; switching languages with cookies or by updating the content in place makes the versions very difficult for Google to handle.
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence transcript
Used byrequirement DEV-INT-01
Each page in an hreflang set must also list its own URL, and a missing self-reference is a common mistake Google sees.
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence transcript
Used byrequirement DEV-INT-03
When the HTML head is not suitable for a page, hreflang can be given by other methods instead, such as listing the language versions in a sitemap.
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence transcript
Used byrequirement DEV-INT-05
Any one hreflang method is fine, but a site should use only one: Google often sees sites using two or three methods at the same time, with annotations that conflict.
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence transcript
Used byrequirement DEV-INT-05
Google ignores hreflang annotations that point only one way, where page A names page B as a language version but page B does not name page A back.
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence transcript
Used byrequirement DEV-INT-03glossary term hreflang return link
Google requires hreflang return links because an alternate URL is a full URL that can be on any domain, so without them any site could declare itself a language version of someone else's website.
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence transcript
Used byrequirement DEV-INT-03
Swedish content for Sweden is marked sv-SE, not se-SE: the language part must be the Swedish language code sv, even though Sweden's country code is SE.
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence transcript, slide photo
Used byrequirement DEV-INT-04
Site owners do not need to memorise hreflang language and region codes, but should double-check every code when implementing hreflang.
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence transcript
Czech is a frequent hreflang error: CZ is the country code and ccTLD of Czechia, but the language code for Czech is cs.
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence transcript, slide photo
Used byrequirement DEV-INT-04
Google does not use hreflang to determine a page's language when indexing the page.
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence transcript
Used byrequirement DEV-INT-07glossary term hreflang
Google said incorrect hreflang language or region codes are a mistake it finds very often, with the same wrong codes coming up again and again, especially in Europe, because site owners assume the codes are easy.
Speaker GoogleIn Day 2, 14:15 · Focusing on Internationalisation and LocalisationEvidence transcript
Used byrequirement DEV-INT-04
In a community speaker's audit case, a premium multifunctional-furniture maker about to be acquired had multilingual sites with clean translations by native speakers and hreflang tags that were in fairly good shape.
Speaker Alizée BaudezIn Day 2, 14:30 · Lightning session G: InternationalisationEvidence transcript
A community speaker framed international SEO around three signals to settle before working on hreflang: language (what people can read), region (who the content is for) and authority (why local people should trust the site).
Speaker Alizée BaudezIn Day 2, 14:30 · Lightning session G: InternationalisationEvidence transcript
A community speaker stressed that an hreflang annotation for a country (her example was German for Austria, de-AT) does not by itself make a site established or trusted in that country; local authority has to be worked for.
Speaker Alizée BaudezIn Day 2, 14:30 · Lightning session G: InternationalisationEvidence transcript
A community speaker cited a Semrush study that found at least one hreflang error on 75% of multilingual websites; the study, reported in February 2017, audited 20,000 sites with several language versions (the speaker recalled it as about five years old).
Speaker Alizée BaudezIn Day 2, 14:30 · Lightning session G: InternationalisationEvidence transcript
A community speaker said the SEO industry has treated hreflang as the hard part of international SEO; hreflang is complicated, but the real hard part is the homework of understanding consumers in each market.
“the hard part is actually doing the homework to understand your consumers”
Speaker Alizée BaudezIn Day 2, 14:30 · Lightning session G: InternationalisationEvidence transcript
The first of three questions to ask before the technical work of international SEO is which languages, and which language variants, the site actually serves, keeping languages and variants apart.
Speaker Alizée BaudezIn Day 2, 14:30 · Lightning session G: InternationalisationEvidence transcript
Google's canonical guide says that for canonicalization Google prefers URLs that are part of hreflang clusters: if German pages for Germany and Switzerland point to each other with hreflang but not to the Austrian page, the German and Swiss pages are preferred as canonicals.
Publisher Google Search CentralAnnotates Day 2, 11:55 · Handling web duplication
Used byrequirement DEV-INT-08
Google's guide to specifying canonical URLs says that on pages using hreflang, the canonical should be a page in the same language, or the best possible substitute language if no canonical page exists in the same language.
Publisher Google Search CentralAnnotates Day 2, 12:05 · Lightning session E: Managing Duplicates and Site Moves
Used byrequirement DEV-CAN-06
Google's hreflang guide says language-specific subdomains such as en, en-gb or de in a URL are not used to determine a page's target audience; site owners must map the audience explicitly, for example with hreflang.
Publisher Google Search CentralAnnotates Day 2, 14:15 · Focusing on Internationalisation and Localisation
Google's hreflang guide says its three methods (link elements in the HTML head, an HTTP Link header, which suits non-HTML files such as PDFs, and an XML sitemap) are equivalent; using several at once is allowed but brings no benefit in Search and is harder to manage.
Publisher Google Search CentralAnnotates Day 2, 14:15 · Focusing on Internationalisation and Localisation
Used byrequirement DEV-INT-05
Google's hreflang guide says a site that finds it hard to keep every language pair bidirectional may omit some languages on some pages, because Google still processes the pairs that point to each other; new language versions should at least link both ways with the original or dominant language.
Publisher Google Search CentralAnnotates Day 2, 14:15 · Focusing on Internationalisation and Localisation
Used byrequirement DEV-INT-03
Google's hreflang guide says alternate URLs must be fully qualified, including the protocol (https://example.com/foo, not //example.com/foo or /foo), and need not be on the same domain.
Publisher Google Search CentralAnnotates Day 2, 14:15 · Focusing on Internationalisation and Localisation
Used byrequirement DEV-INT-03
Google's hreflang guide says pages that translate only the template (navigation, footer) around main content in one language still count as duplicates, because localized versions are duplicates only if the main content stays untranslated; it recommends hreflang for such pages.
Publisher Google Search CentralAnnotates Day 2, 14:15 · Focusing on Internationalisation and Localisation
Used byrequirement DEV-INT-07
Google's hreflang guide says the ISO 639-1 language code can be followed by a script in ISO 15924 format, such as zh-Hant or zh-Hans, and by an optional ISO 3166-1 Alpha-2 region code, as in zh-Hans-US.
Publisher Google Search CentralAnnotates Day 2, 14:15 · Focusing on Internationalisation and Localisation
Used byrequirement DEV-INT-04
Google's documentation recommends hreflang annotations even when a site's versions differ only by small regional variations within one language, for example English-language content targeted to the US, GB and Ireland.
Publisher Google Search CentralAnnotates Day 2, 14:30 · Lightning session G: Internationalisation
Used byrequirement DEV-INT-08
Google's documentation lists the signals it uses to decide which locale a page targets: ccTLDs, hreflang statements, server location, and other signals such as local addresses and phone numbers, local language and currency, links from other local sites and Business Profile signals.
Publisher Google Search CentralAnnotates Day 2, 14:30 · Lightning session G: Internationalisation
Used byrequirement DEV-INT-08
Put rel=canonical and hreflang link elements in the head of the HTML the server sends, not only in JavaScript-rendered HTML, so Google can read them during HTML parsing without depending on rendering.
Author Ibrahim AnjroAnnotates Day 2, 10:25 · How is HTML interpreted
Used byrequirement DEV-CAN-03
For German-language sites serving Germany, Austria and Switzerland, add hreflang with region codes (de-DE, de-AT, de-CH) and make the country pages differ in more than boilerplate (prices, shipping, legal details), or expect Google to cluster them and show one.
Author Ibrahim AnjroAnnotates Day 2, 11:55 · Handling web duplication
Used byrequirement DEV-INT-08
Check that every canonical group contains a single document language: a group spanning languages means canonicals are joining versions that hreflang should connect, and each language version should keep its own self-referencing canonical.
Author Ibrahim AnjroAnnotates Day 2, 12:05 · Lightning session E: Managing Duplicates and Site Moves
Used byrequirement DEV-CAN-06
Audit hreflang per cluster rather than per page: check that every page lists itself and all its alternates, that every alternate links back, and that only one method (HTML head, HTTP header or sitemap) supplies the annotations.
Author Ibrahim AnjroAnnotates Day 2, 14:15 · Focusing on Internationalisation and Localisation
Used byrequirement DEV-INT-03
Validate hreflang values against the ISO 639-1 and ISO 3166-1 Alpha-2 lists in a crawler rule or build check rather than by eye: reserved codes such as UK and EU are simply ignored, but some plausible mistakes are valid codes for something else (se is Northern Sami, GE Georgia, LA Laos, SA Saudi Arabia) and silently point the annotation at the wrong audience.
Author Ibrahim AnjroAnnotates Day 2, 14:15 · Focusing on Internationalisation and Localisation
Used byrequirement DEV-INT-04
Treat hreflang as a way to show the right language version, not as a market-entry signal: before launching a country version, make sure local publications, partners or directories already mention the brand, and localise pricing and payment options.
Author Ibrahim AnjroAnnotates Day 2, 14:30 · Lightning session G: Internationalisation
List language variants such as fr-FR and fr-BE or de-DE and de-CH separately in a site's language inventory, and give each its own vocabulary and spelling review instead of reusing one translation for every country.
Author Ibrahim AnjroAnnotates Day 2, 14:30 · Lightning session G: Internationalisation
Because a brand-only query does not reveal the user's language, Google sometimes struggles to show the right language version of a page for brand searches.
Speaker John MuellerIn Day 3, 10:25 · Making sense of users' queriesEvidence transcript
Used byrequirement DEV-INT-03
Sites with several language versions should not leave brand searches to chance: annotate the versions with hreflang and offer a visible language switcher, because Google may have only the user's location and browser settings to choose a version.
Author Ibrahim AnjroAnnotates Day 3, 10:25 · Making sense of users' queries
Used byrequirement DEV-INT-03
Make each page's language and target country unambiguous (one main language per page, hreflang between versions, local prices, addresses and shipping details), because Google applies language and country already at retrieval, before ranking.
Author Ibrahim AnjroAnnotates Day 3, 10:25 · Making sense of users' queries
Used byrequirement DEV-INT-07
When localized pages are clustered, Google tries to use hreflang alternates; the speaker's short version of the advice was to use hreflang, which he called really helpful for same-language, different-country content.
Google extracts hreflang annotations, through which site owners specify the language variants of their content, to know whether a page has an equivalent with similar content in another language.
A community speaker said language versions need adjusting for regional variants of one language: 90 is 'quatre-vingt-dix' in France but 'nonante' in Belgium, and Swiss German differs from German, for example in whether the letter ß (Eszett) is used.
Language versions can also be language-plus-region variants: Google's example site had a generic English page (en), a UK English page (en-gb) and a Spanish page (es), each on its own URL.
Google said incorrect hreflang language or region codes are a mistake it finds very often, with the same wrong codes coming up again and again, especially in Europe, because site owners assume the codes are easy.
hreflang language codes must be ISO 639-1 codes: Google's list of common mistakes marked se, dk and cz (the country codes of Sweden, Denmark and Czechia) as wrong and sv, da and cs (Swedish, Danish, Czech) as right.
Make hreflang complete: a self-reference, return links and fully qualified URLs
Rests on 12 claims, 10 of them in this topic
Rests on 10 claims, 10 of them in this topic
Differentiate same-language country versions beyond boilerplate and mark them with region codes
Rests on 6 claims, 6 of them in this topic
Do not canonicalise one language version to another; connect them with hreflang
Rests on 4 claims, 4 of them in this topic
Supply hreflang through one method only: HTML head, HTTP Link header or sitemap
Rests on 3 claims, 3 of them in this topic
Make each page's language unambiguous by translating the template with the main content
Rests on 12 claims, 3 of them in this topic
Give every language and country version its own URL
Rests on 4 claims, 2 of them in this topic
Put exactly one absolute rel=canonical in the server-rendered head of every indexable page
Rests on 8 claims, 1 of them in this topic