This post was sponsored by Weglot. The opinions expressed in this article are the sponsor’s own.
The introduction of Google's AI Overviews in 2024 sparked immediate questions among SEO professionals, particularly concerning how websites could maintain visibility when AI curates and summarizes search results across various languages. A recent data-driven study by Weglot offers a compelling answer: translated websites achieve significantly higher visibility in AI Overviews, seeing up to 327% more exposure than their untranslated counterparts. This finding underscores the critical role of multilingual SEO in the evolving landscape of AI-powered search.
The study, which analyzed 1.3 million citations across Google AI Overviews and ChatGPT, found that websites with another language available were more likely to be cited, regardless of the search language. This suggests that international SEO is becoming an inseparable component of any effective AI search strategy.
The Changing Nature of Search
This shift in search behavior is redefining the rules of online visibility. AI Overviews and large language models (LLMs) now mediate how information is discovered. Instead of merely ranking pages, these AI systems "cite" sources within their generated responses. This introduces a new risk for websites: if your content isn't available in the user's search language, AI might overlook it entirely or, worse, direct users to Google Translate's proxy page. The latter scenario means you lose control over your content's translation quality and, crucially, forfeit valuable direct traffic to your site.
Weglot's Data-Driven Study
To understand how translation impacts AI visibility, Weglot focused its research on Spanish-language websites across two key markets: Spain and Mexico. The study was conducted in two phases:
- Phase One: Examined 153 untranslated websites (98 from Spain, 55 from Mexico) that only displayed content in Spanish. High-traffic sites were deliberately chosen to ensure robust data.
- Phase Two: Involved a comparison group of 83 Spanish and Mexican sites that offered versions in both Spanish and English. This allowed for a direct comparison of translated versus untranslated content performance.
The methodology involved converting the top 50 non-branded keywords of each site into likely user queries, which were then translated between Spanish and English versions. In total, the study generated 22,854 queries in phase one and 12,138 in phase two, leading to the analysis of 1.3 million citations.
Key Findings: Untranslated Sites Face Significant Visibility Gaps
The study's findings reveal a substantial drop in visibility for untranslated websites when searches are conducted in non-available languages, even if those sites perform well in their primary language. Untranslated sites effectively disappear from AI search results for queries made in other languages.
- For 98 untranslated sites from Spain, there were 17,094 citations for Spanish queries compared to just 2,810 citations for equivalent English searches – a staggering 431% visibility gap.
- Mexican untranslated sites showed a similar pattern, with 12,038 citations for Spanish queries versus 3,450 for English, indicating 213% fewer citations in English searches.
Even ChatGPT, while slightly more balanced, still favored translated sites, with Spanish sites receiving 3.5% fewer citations in English and Mexican sites 4.9% fewer.
Translated Sites See 327% More AI Search Visibility
The picture changes dramatically for translated sites. The comparison group of Spanish websites with English versions demonstrated that having a second language significantly closed the visibility gap within Google AI Overviews:
- Translated sites in Spain saw 10,046 citations in Spanish versus 8,048 in English, reducing the gap to only 22%.
- Translated sites in Mexico showed 5,527 citations for Spanish queries and 3,325 for English, a difference of 59%.
Overall, translated sites achieved 327% more visibility than untranslated ones and earned 24% more total citations per query. For ChatGPT, the bias almost vanished, with translated sites receiving near-equal citations in both languages.
Next Steps: Translate Your Site for Global AI SERP Visibility
The study clearly indicates that translation does more than just boost visibility; it multiplies it. Having multiple languages on your site ensures it's picked up for searches in those languages and enhances its overall visibility. Translated sites performed better across all metrics, receiving 24% more citations per prompt than untranslated sites. Breaking this down by language, translation resulted in a 33% increase in English citations and a 16% increase in Spanish citations per query.
Weglot's findings suggest that translation acts as a signal of authority and reliability for AI Overviews and ChatGPT, boosting citation performance across all languages, not just the ones content is translated into.
AI Search Rewards Translated Content as a Visibility Signal
While traditional international SEO has focused on hreflang tags and localized keywords, the age of AI search elevates translation itself into a crucial visibility signal:
- Language Alignment: AI engines prioritize content that directly matches the query's language.
- Authority Building: Translated content attracts engagement across diverse markets, enhancing perceived reliability and authority.
- Traffic Control: Proper translations prevent Google Translate proxies from intercepting clicks, ensuring users land directly on your site.
- Semantic Reach: Multilingual content broadens your site's surface area for AI training and citation, increasing its chances of being referenced.
Simply put: if your content isn't in the language of the question, it's unlikely to appear in the AI-generated answer.
The Business Impact
The consequences of neglecting translation are not theoretical. A case from Weglot's dataset involved a major Spanish book retailer selling English-language titles worldwide but without an English version of its website. When English speakers searched for relevant books:
- The site appeared 64% less often in Google AI Overviews and ChatGPT.
- In 36% of its appearances, the link pointed to Google Translate's proxy, not the retailer's own domain.
Despite offering exactly what English users sought, the business suffered significant losses in visibility, traffic, and ultimately, sales.
The Bigger Picture: AI Search Redefines SEO, Translation Becomes a Growth Strategy
The implications of this study extend far beyond specific languages or regions. As AI search continues to evolve, the SEO playbook is expanding. Ranking is no longer solely about achieving "position one" in traditional search results; it's about being cited, summarized, and surfaced by AI models trained on multilingual web content.
Weglot's findings point to a future where translation is not merely a localization afterthought but a fundamental SEO and AI strategy. With Google AI Overviews now live in multiple languages and ChatGPT integrating real-time web data, multilingual visibility has become an equity issue: sites optimized for only one language risk becoming invisible to a significant portion of the global audience.
Final Takeaway: Untranslated Sites Are Invisible in AI Search
The evidence is clear: untranslated content is largely unseen by AI search. Website translation is paramount for AI Overview visibility. As AI continues to shape how search engines understand relevance, translation is not just about accessibility; it's how your brand gains recognition from both algorithms and diverse audiences worldwide.
For those looking to easily translate their website, Weglot offers a free trial. Additionally, users can enjoy a 15% discount for 12 months on public plans by using the promo code SEARCH15 on a paid plan purchase.
