Large-Scale Online Deanonymization with LLMs

We measure the capabilities of LLMs to deanonymize users online.

Large-Scale Online Deanonymization with LLMs We measure the capabilities of LLMs to deanonymize users online. Simon Lermen Feb 24, 2026 52 5 8 Share TL;DR: We show that LLM agents can figure out who you are from your anonymous online posts. Across Hacker News, Reddit, LinkedIn, and anonymized interview transcripts, our method identifies users with high precision – and scales to tens of thousands of candidates. While it has been known that individuals can be uniquely identified by surprisingly few attributes, this was often practically limited. Data is often only available in unstructured form

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