ChatGPT's .co.jp Citation Rate Hits 44.8% in Optyino.ai Survey
Japanese companies seeking visibility in AI-generated answers now have evidence that ChatGPT skews toward .co.jp and .jp domains, while Google AI Overview favors .com, meaning GEO strategies must be tailored to each model's citation patterns.
Reporting from 1 source: ASCII.jp.
Optyino.ai analyzed 71,041 AI responses across 585 prompts and found that .co.jp domains accounted for 35.5% of all cited URLs, behind .com at 40.2%. ChatGPT cited .co.jp at 44.8%, the highest among major models, while Google AI Overview led in .com citations at 46.7%. The top three domain attributes-.com, .co.jp, and .jp-made up 94.9% of cited URLs.
Optyino.ai, a GEO visualization platform, analyzed 585 prompts across industries from finance to Web3.0, collecting 71,041 AI responses between August 2025 and June 2026. The 134,174 cited URLs were then broken down by domain attribute. The overall leader was .com at 40.2%, but .co.jp followed at 35.5% and .jp at 19.2%. The real story is in the model-by-model difference: ChatGPT cited .co.jp at 44.8% and .jp at 23.9%, for a combined 68.7% Japanese-domain rate. Google AI Overview, by contrast, cited .com at 46.7% and .co.jp at only 28.7%. Claude sat in the middle with a .co.jp rate of 37.1%.
Synthesized by Yomimono from the 1 cited source below, including Japanese-language reporting where cited, then editorially reviewed before publishing.