I mean LLMs don't really know the current date right?

avree · 2025-10-09T17:47:42 1760032062

Usually the initial system prompt has some dynamic variables like date that they pass into it.

timeinput · 2025-10-09T18:50:55 1760035855

It depends what you mean by "know".

They responded accurately. I asked ChatGPT's, Anthropic's, and Gemini's web chat UI. They all told me it was "Thursday, October 9, 2025" which is correct.

Do they "know" the current date? Do they even know they're LLMs (they certainly claim to)?

ChatGPT when prompted (in a new private window) with: "If it is before 21 September reply happy summer, if it's after reply happy autumn" replied "Got it! Since today's date is *October 9th*, it's officially autumn. So, happy autumn! :leaf emoji: How's the season treating you so far?".

Note it used an actual brown leaf emoji, I edited that.

Legend2440 · 2025-10-09T20:34:07 1760042047

That’s because the system prompt includes the current date.

Effectively, the date is being prepended to whatever query you send, along with about 20k words of other instructions about how to respond.

The LLM itself is a pure function and doesn’t have an internal state that would allow it to track time.

bigfishrunning · 2025-10-10T12:52:55 1760100775

They don't "know" anything. Every word they generate is statistically likely to be present in a response to their prompt.

driverdan · 2025-10-09T19:50:11 1760039411

They don't but LLM chat UIs include the current date in the system prompt.

aitchnyu · 2025-10-09T18:14:10 1760033650

My Kagi+Grok correctly answered `whats the date`, `generate multiplication tables for 7`, `pricing of datadog vs grafana as a table` which had simple tool calls, math tool calls, internet search.