Knowledge Boundary of Large Language Models: A Survey
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Abstract (arXiv)
Although large language models (LLMs) store vast amount of knowledge in their parameters, they still have limitations in the memorization and utilization of certain knowledge, leading to undesired behaviors such as generating untruthful and inaccurate responses. This highlights the critical need to understand the knowledge boundary of LLMs, a concept that remains inadequately defined in existing research. In this survey, we propose a comprehensive definition of the LLM knowledge boundary and introduce a formalized taxonomy categorizing knowledge into four distinct types. Using this foundation, we systematically review the field through three key lenses: the motivation for studying LLM knowledge boundaries, methods for identifying these boundaries, and strategies for mitigating the challenges they present. Finally, we discuss open challenges and potential research directions in this area. We aim for this survey to offer the community a comprehensive overview, facilitate access to key issues, and inspire further advancements in LLM knowledge research.
Key facts. Cited by 38 papers in the map (data through 13 Oct 2026). Builds on 141 of its 181 references that are in the map. First posted on arXiv 17 Dec 2024.
Builds on
141 of 181 references.
References · 141
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50 most cited of 141 All 141 (JSON)
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Citing papers per year: 2025: 19; 2026: 19.
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- 2026LittleLearner: Language Models Under Pedagogically Controlled Knowledge Exposure13 Aug 2026
- 2026KBF: Knowledge Boundary as Fingerprint for Language Model and Black-Box API Auditing28 May 2026
- 2026Neurosymbolic Learning for Inference-Time Argumentation19 May 2026
- 2026GRADE: Probing Knowledge Gaps in LLMs through Gradient Subspace Dynamics3 Apr 2026
- 2026KA2L: A Knowledge-Aware Active Learning Framework for LLMs18 Mar 2026
- 2026Know More, Know Clearer: A Meta-Cognitive Framework for Knowledge Augmentation in Large Language Models13 Feb 2026
- 2026Deep Learning-based Method for Expressing Knowledge Boundary of Black-Box LLM11 Feb 2026
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- 2025Assessing the Software Security Comprehension of Large Language Models24 Dec 2025
- 2025LORE: A Large Generative Model for Search Relevance2 Dec 2025
- 2025Context-Aware Pragmatic Metacognitive Prompting for Sarcasm Detection26 Nov 2025
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