This study evaluates the UN Sustainable Development Goals (SDGs) literacy and intelligence of ChatGPT, a large language model (LLM) developed by OpenAI. The research uses two widely used sustainability assessment tests—SULITEST and the UN SDG Fitness Test—to gauge ChatGPT's understanding of the SDGs. The results indicate that ChatGPT exhibits high SDG literacy, scoring 85% on the SDG Fitness Test and 97.5% on the SULITEST. However, its comprehensive SDG intelligence requires further exploration. The study finds that while ChatGPT maps all eight key SDG competencies across 24 questions in the SDG Fitness Test, it struggles with specific SDGs such as 6, 12, and 15, which are underrepresented in the test. Similarly, the SULITEST questions map to SDG competencies but do not provide detailed performance levels. The study concludes that while AI models like ChatGPT hold significant potential in sustainable development, their usage must be approached with caution, considering current limitations and ethical implications. Future versions of ChatGPT should enhance competencies such as collaboration, critical thinking, and systems thinking to better support the SDGs.This study evaluates the UN Sustainable Development Goals (SDGs) literacy and intelligence of ChatGPT, a large language model (LLM) developed by OpenAI. The research uses two widely used sustainability assessment tests—SULITEST and the UN SDG Fitness Test—to gauge ChatGPT's understanding of the SDGs. The results indicate that ChatGPT exhibits high SDG literacy, scoring 85% on the SDG Fitness Test and 97.5% on the SULITEST. However, its comprehensive SDG intelligence requires further exploration. The study finds that while ChatGPT maps all eight key SDG competencies across 24 questions in the SDG Fitness Test, it struggles with specific SDGs such as 6, 12, and 15, which are underrepresented in the test. Similarly, the SULITEST questions map to SDG competencies but do not provide detailed performance levels. The study concludes that while AI models like ChatGPT hold significant potential in sustainable development, their usage must be approached with caution, considering current limitations and ethical implications. Future versions of ChatGPT should enhance competencies such as collaboration, critical thinking, and systems thinking to better support the SDGs.