> ## Documentation Index
> Fetch the complete documentation index at: https://docs.peec.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# ChatGPT searches in English even when users don't

> Peec analysed 10M+ prompts and 20M fan-outs (Feb 2026) — 78% of non-English ChatGPT sessions include English sub-searches, and 43% of all fan-outs for non-English prompts run in English.

ChatGPT conducts much of its background research in English regardless of the user's language. Peec analyzed over 10 million prompts and 20 million query fan-outs, filtered to cases where user location matched query language — Polish queries from Poland, German from Germany, Spanish from Spain ([full study](https://peec.ai/blog/chatgpt-searches-in-english-even-when-you-don-t), Feb 2026).

* **In nearly 78% of non-English cases**, ChatGPT supplements the query with additional English-language research; across all non-English sessions analyzed, at least one sub-search hits the English web.
* **43% of all fan-out research steps** for non-English prompts run in English.
* By language: Turkish switches most at 94%, Spanish least at 66% — no non-English language falls below 60% (Feb 2026 data).

The consequence: local market leaders lose to global brands in their home market. Documented examples include German software queries returning zero German companies, and Allegro.pl (Poland's dominant marketplace) missing from Polish auction-portal answers while eBay ranks. ChatGPT even rewrote a Spanish cosmetics query into "top *global* cosmetic brands" on its own.

Why: English content carries more authority signals (backlinks, citations), and with \~50% of internet content in English, English queries reduce retrieval risk. What to do: identify which English sources ChatGPT trusts in your category and get present in them — strategic English content beats blind translation. Google's surfaces stay closer to the query language — see [Optimizing for Google AI vs ChatGPT](/research/optimizing-google-ai-vs-chatgpt) and [Translated Reddit citations](/research/reddit-translated-citations).

**Source:** [ChatGPT searches in English, even when you don't](https://peec.ai/blog/chatgpt-searches-in-english-even-when-you-don-t), Peec (Tomek Rudzki), Feb 2026.