A ChatGPT answer in Portuguese cites 1.94 websites on average, 29.2% fewer than the 2.74 in a US English answer, and every other language tested also gets fewer sources. ChatGPT gives no sources at all in 8% of Portuguese answers, against 1.7% in US English.
Analysis of 14,000 ChatGPT and Gemini answers in six languages · ChatGPT and Gemini, September 2026
Key Findings
- 1.ChatGPT answers in Portuguese cite 1.94 websites on average, 29.2% fewer than the 2.74 in US English answers.
- 2.ChatGPT answers in German cite 2.08 websites on average, 24.1% fewer than in US English, while Spanish and French answers cite 2.31, 15.7% fewer.
- 3.ChatGPT gives no sources at all in 8% of its Portuguese answers and 6.9% of its German ones, against 1.7% of US English answers.
- 4.Gemini gives no sources in 52.2% of its German answers and 48.9% of its French answers, against 38.8% in US English.
- 5.ChatGPT's German answers are the shortest of any language, about 122 words against 201 in US English.
Summary
A gym-goer in São Paulo asks ChatGPT, in Portuguese, the best time of day to take creatine. An American asking ChatGPT in English typically gets nearly three sources to check. The Brazilian gets fewer than two, and one Portuguese answer in twelve has no sources at all.
Sources are the citations an AI answer shows as evidence, and they are how AI sends readers, and credit, to websites. For a publisher or brand outside the English-speaking world, fewer sources per answer means fewer places to be cited and a reader with less to verify.
ChatGPT cites 29.2% fewer websites in Portuguese than in US English, 1.94 against 2.74, and every non-English language tested falls below every English market. Gemini behaves differently. Its source counts are flat across languages, but it gives no sources at all in 38.8% of its US English answers and over half of its German ones.
What we measured
On September 23, 2026 we asked ChatGPT and Gemini 150 popular questions in each of Portuguese, German, Spanish, French and Italian, taken from what people search for in those languages, such as "welches ist das beste magnesium" and "qual melhor horário para tomar creatina". We also asked 500 English questions with the location set to the US, the UK, Canada and Australia. Every question was asked twice on each engine, giving 14,000 answers.
For each answer we counted the sources: the distinct websites it cites, so a site linked twice counts once. We also recorded the share of answers that cite no website at all and the length of the answer in words, and compared each language with US English.
Fewer sources in every language on ChatGPT
English answers cluster between 2.56 and 2.74 sources whatever the country. Every other language falls below that range: Spanish and French at 2.31, Italian at 2.22, German at 2.08 and Portuguese at 1.94. Because the four English markets barely differ, the drop follows the language of the question, not the location of the person asking.
Source: Suff Digital analysis of 14,000 ChatGPT and Gemini answers in six languages · ChatGPT and Gemini, September 2026
| Language or market | ChatGPT sources per answer | ChatGPT answers with no sources | ChatGPT answer length (words) |
|---|---|---|---|
| English (US) | 2.74 | 1.7% | 201 |
| English (UK) | 2.67 | 1.6% | 209 |
| English (Canada) | 2.60 | 1.8% | 191 |
| English (Australia) | 2.56 | 1.6% | 189 |
| Spanish | 2.31 | 6.8% | 145 |
| French | 2.31 | 5.2% | 152 |
| Italian | 2.22 | 5.7% | 153 |
| German | 2.08 | 6.9% | 122 |
| Portuguese | 1.94 | 8% | 131 |
Answers with no sources become far more common. Under 2% of ChatGPT's English answers cite nothing, against 5.2% to 8% in the other languages, so a Portuguese answer is almost five times as likely to arrive without a single source. The answers also get shorter, from 201 words in US English to 131 in Portuguese and 122 in German. ChatGPT cites less and writes less when the question is not in English.
Gemini is flat, but often cites nothing
Gemini's source counts barely move by language, from 1.69 in French to 2.23 in Italian, against 1.83 in US English. In Portuguese (1.98) and Italian it even edges past ChatGPT. The language gap in source counts is a ChatGPT pattern.
Source: Suff Digital analysis of 14,000 ChatGPT and Gemini answers in six languages · ChatGPT and Gemini, September 2026
| Language or market | Gemini sources per answer | Gemini answers with no sources | Gemini answer length (words) |
|---|---|---|---|
| English (US) | 1.83 | 38.8% | 301 |
| English (UK) | 2.15 | 34.8% | 310 |
| Spanish | 1.72 | 38.5% | 231 |
| Italian | 2.23 | 37% | 274 |
| Portuguese | 1.98 | 41.5% | 241 |
| French | 1.69 | 48.9% | 248 |
| German | 1.79 | 52.2% | 188 |
Gemini's weakness is the answers with no sources at all, and it is large in every language: 38.8% of its US English answers cite nothing, rising to 48.9% in French and 52.2% in German. More than half of Gemini's German answers give the reader no website to check. Gemini's answers shrink outside English too, from about 301 words in US English to 188 in German, a drop about as steep as ChatGPT's.
What this means for international publishers and brands
In non-English markets, fewer sources means fewer slots. A ChatGPT answer in Portuguese or German cites about two websites, so the competition for each citation is tighter than in English, and the sites that win it are the ones that answer the question directly in the local language. Local-language pages built around the questions your market actually asks matter more there, not less.
Do not assume your English AI visibility carries over. Ask your customers' questions in their language on ChatGPT and Gemini, several times, and note which local websites win the few citations on offer; those are the sites to earn coverage on. As an international seo agency, Suff Digital tracks AI citations market by market and language by language.
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<p style="font:14px/1.5 system-ui,sans-serif">Source: <a href="https://www.suffdigital.com/resources/data-studies/ai-cites-fewer-sources-other-languages">ChatGPT Cites 29% Fewer Sources in Portuguese Than in English - Suff Digital</a></p>
Cite this study
Suff Digital. (2026). ChatGPT Cites 29% Fewer Sources in Portuguese Than in English. https://www.suffdigital.com/resources/data-studies/ai-cites-fewer-sources-other-languages
ChatGPT Cites 29% Fewer Sources in Portuguese Than in English - Suff Digital - https://www.suffdigital.com/resources/data-studies/ai-cites-fewer-sources-other-languages
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