Use this skill when optimizing websites for multiple countries or languages - hreflang tag implementation, URL structure strategy (ccTLD vs subdomain vs subdirectory), geo-targeting in Google Search Console, multilingual content strategy, and international site architecture. Triggers on multi-language sites, multi-region targeting, hreflang debugging, or expanding a site to new markets.
Use this skill when optimizing websites for multiple countries or languages - hreflang tag implementation, URL structure strategy (ccTLD vs subdomain vs subdirectory), geo-targeting in Google Search Console, multilingual content strategy, and international site architecture. Triggers on multi-language sites, multi-region targeting, hreflang debugging, or expanding a site to new markets.
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International SEO
International SEO ensures search engines serve the right language or regional version
of your content to the right users. It involves URL structure decisions, hreflang
implementation, and content localization strategy that affects how Google treats
multi-market websites. Getting these signals wrong causes duplicate content issues,
wrong-language rankings, and cannibalization between regional variants. Done correctly,
international SEO gives each market its own clear identity and ranking potential.
When to use this skill
Trigger this skill when the user:
Needs to implement hreflang tags for a multi-language or multi-region site
Is choosing a URL structure (ccTLD, subdomain, or subdirectory) for international expansion
Wants to configure geo-targeting in Google Search Console
Is launching a multilingual site or adding a new language/region
Has international duplicate content problems (same content indexed in multiple languages)
Is expanding an existing site into new geographic markets
Single-language, single-region sites with no plans for international expansion
General on-page SEO or technical SEO not related to international targeting
Key principles
Language and country targeting are different things - hreflang="en" targets
English speakers regardless of location. hreflang="en-GB" targets English speakers
in the UK. Use language-only tags when content differs by language but not region;
use language+region tags when content varies by country (pricing, currency, regulations).
hreflang is a signal, not a directive - Google may ignore hreflang if it finds
stronger contradicting signals (canonicals, internal links, server location). Treat
it as a strong hint, not a guarantee. Pair it with consistent internal linking and
correct canonical tags.
URL structure is an architecture decision with trade-offs - ccTLDs give the
strongest geo-signal but require maintaining separate domains. Subdomains are flexible
but split domain authority. Subdirectories are easiest to manage and consolidate
authority but give weaker geo-signals. Choose based on budget, team capacity, and
how distinct each market's content really is.
Translate AND localize - not just translate - Machine-translated content that
retains the source culture (idioms, examples, currency, date formats) fails users
and often fails search. Localization means adapting for the market, not just the
language.
Every language version needs a bidirectional hreflang set - If page A has an
hreflang pointing to page B, page B must have a matching hreflang pointing back to
page A. Asymmetric hreflang is one of the most common implementation errors and
causes Google to ignore the entire annotation set.
Core concepts
Language vs country targeting - ISO 639-1 language codes (en, fr, de) specify
language. ISO 3166-1 alpha-2 country codes (US, GB, FR) specify country. Combine
them as language-COUNTRY (e.g., en-US, fr-FR, pt-BR). Use language-only tags
for content that's the same across countries for that language; use language+country
only when content genuinely differs by market.
hreflang tag syntax - The rel="alternate" link element with an hreflang
attribute tells Google which URL serves which audience. Tags can appear in the HTML
<head>, HTTP response headers, or XML sitemaps. All three methods are equivalent;
choose based on your CMS and hosting setup.
x-default - The x-default hreflang value designates a fallback URL for users
whose language/region isn't explicitly targeted. This is typically your homepage or
a language-selector page. Every hreflang implementation must include an x-default tag
or Google may treat the annotation set as incomplete.
URL structure options - Three canonical approaches exist: ccTLD (example.de),
subdomain (de.example.com), subdirectory (example.com/de/). Each has distinct
trade-offs around domain authority, geo-signal strength, and operational complexity.
See references/url-structure-strategy.md for a full decision matrix.
Geo-targeting signals - Google uses multiple signals to determine regional relevance:
ccTLD, Google Search Console geo-targeting setting, server IP location, hreflang tags,
content language, local addresses and phone numbers, internal links. hreflang is the
most precise signal for language+country combinations.
Content localization vs translation - Translation converts words between languages.
Localization adapts the full user experience: currency, units, legal disclaimers, local
references, cultural tone, and imagery. For SEO, localized content performs better
because it matches local search intent and terminology.
International duplicate content - When two pages serve the same content in the
same language but for different regions (e.g., en-US and en-GB with 95% identical
text), Google may consolidate them and pick one arbitrarily. Use hreflang to tell
Google they're intentional variants, not duplicates.
Common tasks
Implement hreflang tags in HTML head
Add <link rel="alternate"> tags in the <head> of every page. Every page must
reference itself and all its variants, including x-default.
<head><!-- Self-referencing hreflang is required --><linkrel="alternate"hreflang="en-US"href="https://example.com/en-us/pricing/" /><linkrel="alternate"hreflang="en-GB"href="https://example.com/en-gb/pricing/" /><linkrel="alternate"hreflang="de"href="https://example.com/de/pricing/" /><linkrel="alternate"hreflang="fr"href="https://example.com/fr/pricing/" /><!-- x-default is required - points to language selector or most generic version --><linkrel="alternate"hreflang="x-default"href="https://example.com/pricing/" /></head>
Key rules:
Use absolute URLs, not relative paths
Every listed page must have a reciprocal set pointing back to all others
Language codes are case-insensitive but country codes are conventionally uppercase
Include the current page in its own hreflang set (self-reference)
Implement hreflang in XML sitemap
For large sites, managing hreflang in HTML heads is error-prone. XML sitemaps are
easier to generate programmatically and don't require touching every template.
Next.js 13+ renders these as <link rel="alternate"> tags automatically.
Choose URL structure
Use this decision matrix when selecting a URL strategy for international expansion:
Factor
ccTLD (example.de)
Subdomain (de.example.com)
Subdirectory (example.com/de/)
Geo-signal strength
Strongest
Medium
Weak (relies on GSC setting)
Domain authority
Separate per domain
Partially shared
Fully consolidated
Cost
High (register each TLD)
Low
Low
Operational complexity
High (separate infra)
Medium
Low
CDN/hosting
Per-domain setup needed
Flexible
Easiest
Best for
Large, well-funded, market-committed
Flexible mid-size
Single-domain consolidation
Recommendation for most teams: subdirectory unless you have dedicated country-level
marketing budgets and teams. See references/url-structure-strategy.md for migration
paths and server configuration.
Set up geo-targeting in Google Search Console
Geo-targeting in GSC is required for generic TLDs (.com, .io, .co) and subdomains.
It is NOT available for ccTLDs (they inherit targeting from the TLD).
Steps:
Open Google Search Console and select the property (subdomain or subdirectory)
Navigate to Settings > International Targeting
Under "Country", select the target country from the dropdown
Click Save
Important constraints:
You can set one country target per Search Console property
Subdirectory properties inherit the root domain property's setting by default
This setting is a hint, not a hard gate - hreflang still takes precedence for language
Remove the setting if the site serves a global audience (leave it blank)
Handle international duplicate content
When en-US and en-GB pages are nearly identical, use hreflang to declare them as
intentional variants rather than letting Google pick a canonical arbitrarily.
<!-- On en-US page --><linkrel="canonical"href="https://example.com/en-us/page/" /><linkrel="alternate"hreflang="en-US"href="https://example.com/en-us/page/" /><linkrel="alternate"hreflang="en-GB"href="https://example.com/en-gb/page/" /><linkrel="alternate"hreflang="x-default"href="https://example.com/page/" /><!-- On en-GB page - canonical points to itself, not en-US --><linkrel="canonical"href="https://example.com/en-gb/page/" /><linkrel="alternate"hreflang="en-US"href="https://example.com/en-us/page/" /><linkrel="alternate"hreflang="en-GB"href="https://example.com/en-gb/page/" /><linkrel="alternate"hreflang="x-default"href="https://example.com/page/" />
Never point both pages to the same canonical - that tells Google one of them is
a duplicate to be suppressed, defeating the purpose of separate regional pages.
Debug hreflang errors
Common errors reported in Google Search Console under Enhancements > International
Targeting:
Error
Cause
Fix
Return tag missing
Page A references B but B doesn't reference A back
Add reciprocal tags to all referenced pages
Unknown language tag
Invalid ISO 639-1 or 3166-1 code used
Check codes against ISO lists; en-uk is wrong, use en-GB
No x-default
hreflang set exists but no x-default tag
Add hreflang="x-default" to a fallback URL
Multiple hreflang for same locale
Same language+country code appears twice on a page
Remove duplicate; keep only one tag per locale
HTTP errors on hreflang URLs
Linked pages return 4xx/5xx
Fix pages or update hreflang to point to live URLs
Use the hreflang Testing Tool (hreflang.org) or Screaming Frog to audit at scale.
Anti-patterns / common mistakes
Anti-pattern
Why it's wrong
What to do instead
Auto-redirect by IP/browser language
Hides content from Googlebot (which crawls from US IPs) - regional versions won't get indexed
Show all versions to all crawlers; use hreflang to signal preference, let users choose
Machine-translated content without review
Produces unnatural text that matches no real search queries, penalized by quality algorithms
Use professional or post-edited machine translation; localize beyond just words
Missing x-default
hreflang set treated as incomplete by Google; fallback users land on wrong-language page
Always include hreflang="x-default" pointing to a language-selector or default locale
Asymmetric hreflang
If A lists B but B doesn't list A, Google ignores the entire annotation set
Every page in a group must list ALL other pages in that group
Using wrong locale codes
en-UK, zh-CN (wrong capitalization), sp (not a valid ISO code)
Use ISO 639-1 for language (en, zh, es) and ISO 3166-1 alpha-2 for country (GB, CN, ES)
Pointing hreflang to redirected or canonicalized URLs
Google may not follow the chain; annotations on redirected pages are ignored
Always use the final canonical URL in hreflang tags
One sitemap hreflang, one HTML hreflang
Mixed implementation creates conflicting signals
Choose one method and implement it consistently across the entire site
Gotchas
Auto-redirecting users by IP or Accept-Language hides content from Googlebot - Googlebot crawls from US IP addresses. If your site redirects non-US IPs to regional variants, Googlebot sees only the English-US version and never indexes your German, French, or Spanish pages. Show all language versions to all crawlers without redirects; use hreflang to express the preference.
Hreflang in sitemap and HTML head simultaneously creates conflicting signals - If you implement hreflang in your XML sitemap and also have <link rel="alternate"> tags in the HTML head pointing to different URLs (e.g., the sitemap uses trailing slashes and the HTML doesn't), Google may discard the entire annotation set. Choose one implementation method and make it consistent across the entire site.
Using the wrong canonical with regional variants tells Google to suppress one variant - On an en-GB page, if the canonical points to the en-US page, Google treats en-GB as a duplicate and eventually stops indexing it entirely. Each regional variant must have a canonical pointing to itself, paired with hreflang indicating it's an intentional variant.
Subdirectory geo-targeting in GSC only applies to the root property, not subdirectories - Google Search Console geo-targeting settings apply to the property you configure, which for a root domain includes all subdirectories. You cannot set example.com/de/ to target Germany and example.com/fr/ to target France through GSC - that's what hreflang is for. GSC targeting is for the top-level property only.
Machine-translated content with source-language URL slugs ranks poorly in target markets - Translating page content but keeping URL slugs in English (e.g., /de/how-to-use-software/) means the URL provides no language signal and local search queries don't match. Localize slugs along with content: /de/software-verwenden/ performs better and avoids mixed-signal confusion.
References
For detailed content on specific topics, read the relevant file from references/:
references/hreflang-implementation.md - Complete hreflang guide: HTML/HTTP/sitemap
syntax, valid codes, x-default usage, framework-specific implementation (Next.js,
Nuxt), paginated content, and Search Console debugging. Load when implementing or
auditing hreflang.
references/url-structure-strategy.md - Detailed comparison of ccTLD vs subdomain
vs subdirectory with SEO implications, domain authority consolidation, hosting and
CDN considerations, server configuration (Apache/Nginx), and migration paths. Load
when choosing or changing URL structure for international sites.
Only load a references file if the current task requires deep detail on that topic.
Companion check
On first activation of this skill in a conversation: check which companion skills are installed by running ls ~/.claude/skills/ ~/.agent/skills/ ~/.agents/skills/ .claude/skills/ .agent/skills/ .agents/skills/ 2>/dev/null. Compare the results against the recommended_skills field in this file's frontmatter. For any that are missing, mention them once and offer to install:
