Can using local characters in URLs harm your SEO performance?

Does Google really treat all alphabets the same?

Yes, according to Mueller. The engine supports UTF-8 natively, allowing it to crawl, index, and rank URLs featuring Cyrillic, Chinese ideograms, Arabic, or Greek. The bot applies no preference filter for Latin characters.

This means an URL like example.fr/produits/café or example.jp/商品/カメラ will be processed without structural bias. Google will not rewrite the URL internally, will not convert it to ASCII before indexing, and will not assign it less weight than an equivalent Latin URL.

Why does this question frequently arise among SEOs?

Because for years, the default advice was to systematically transliterate URLs: replacing accents, converting Cyrillic to Latin, and avoiding any non-ASCII character. Historically, some older browsers poorly encoded UTF-8, turning URLs into unreadable strings.

As a result, a Cyrillic URL would become a sequence like %D0%9F%D1%80%D0%BE%D0%B4%D1%83%D0%BA%D1%82 in the address bar. Horrible for UX, disastrous for social sharing. This fear ingrained the reflex “Latin characters = safety,” even though technically Google has never penalized UTF-8.

What does it mean when we say “does not affect rankings”?

This means no direct ranking signal is assigned based on the character set of the URL. No boost for Latin, no penalty for Japanese. The content of the URL is still analyzed to understand the page's theme, but the scoring system does not discriminate based on the alphabet.

Be careful: this does not imply there are no indirect consequences. If a URL with local characters is poorly shared on Twitter, LinkedIn, or via email (broken encoding, truncated links), the click-through rate may drop. Google does not directly measure external CTR, but fewer visits = fewer behavioral signals = potential SEO impact.

• UTF-8 is supported by Googlebot without alphabet restrictions.
• No algorithmic penalties exist for URLs with non-Latin characters.
• Indirect impacts (UX, sharing, technical compatibility) are real and measurable.
• Older browsers and certain platforms still poorly encode UTF-8, creating unreadable %encoded URLs.
• Google can semantically analyze the keywords present in the URL, regardless of the alphabet used.

Is Google's position consistent with field observations?

Yes, in terms of pure indexing. Russian, Chinese, and Arabic sites using local URLs are indexed and ranked normally. No correlation studies have ever shown systematic penalties related to the use of non-Latin characters in slugs.

However, problems arise elsewhere: some CMS (WordPress, Drupal) automatically convert UTF-8 URLs to Punycode or percent-encoding at generation, creating double URLs (canonical in UTF-8, displayed in %encoded). Google handles these cases, but it complicates crawling and may dilute internal link signals if anchors point to differently encoded versions.

What gray areas are not covered by this statement?

Mueller doesn’t clarify anything regarding subdomains and internationalized domains (IDN). A domain like кафе.рф (café.rf in Cyrillic) will be converted to xn--80aae8bj.xn--p1ai by the DNS system. Google crawls it, but the display in SERPs may vary based on the user's location and browser configuration.

Another blind spot: the impact on crawl budget. If a site generates thousands of URLs with poorly normalized special characters (spaces, multiple accents, exotic Unicode combinations), Googlebot may encounter technical duplicates. [To verify]: No official data confirms that complex UTF-8 slows crawl speed, but empirically, some logs show repeated recrawls on URLs with unstable Unicode normalization.

When should local characters still be avoided?

When the target audience heavily relies on email or messaging sharing. Email clients (Outlook, Thunderbird) poorly manage UTF-8 in clickable links: the URL appears broken, and the link fails. For a Russian B2B e-commerce site, this can kill virality.

Another case: third-party APIs and tracking. Google Analytics, Matomo, or some BI tools may log %encoded URLs, making reports unreadable. Technically resolved by view filters, but this introduces analytical friction. If your client desires clean dashboards without heavy technical configuration, using Latin remains safer.

Should I migrate from Latin URLs to local URLs to enhance SEO?

No. Mueller explicitly states that there is no preference, so no ranking gains are expected. Migration generates 301 redirects, a risk of temporary loss of positions, and a technical burden (updating internal links, sitemaps, rewriting server rules).

The only valid reason for switching to UTF-8 would be a measurable UX gain: if your users copy-paste URLs into documents, chats, or local social networks that manage UTF-8 well, the URL in native characters is more readable and reassuring. However, this is not a pure SEO criterion.

How can I check if my site properly handles UTF-8 in URLs?

Start by inspecting your .htaccess or nginx.conf file: the directive AddDefaultCharset UTF-8 should be present. Also, check the HTTP headers: Content-Type: text/html; charset=UTF-8 should be sent by the server.

Next, test a slug containing local characters in Search Console: submit it via the URL Inspection tool. If Google crawls it without error and displays the URL correctly in the coverage report, you're good. If the URL appears %encoded in the console while your CMS shows it in UTF-8, you have a normalization issue to resolve server-side or in the CMS.

What common mistakes should be avoided with special characters?

Never mix multiple encodings within the same site. If you use UTF-8 for some pages and ISO-8859-1 for others, Google will crawl inconsistent versions and may index duplicates with display errors.

Also, avoid non-encoded spaces in slugs. Even though UTF-8 technically supports them, some servers replace them with %20, others with +, creating canonical variants. Always replace spaces with hyphens (-) when generating URLs, regardless of the alphabet used.

• Ensure your server properly sends charset=UTF-8 in the HTTP headers.
• Test URLs with special characters in Search Console to detect crawl errors.
• Audit your backlink profile: identify links pointing to %encoded versions and redirect them if necessary.
• Configure your CMS to consistently normalize UTF-8 URLs (no duplication between UTF-8 and %encoded).
• Avoid spaces, tabs, and exotic Unicode characters (emoji, symbols) in slugs.
• Document the decision (UTF-8 or Latin) in your editorial guidelines to prevent future inconsistencies.