AI

Context window

The maximum amount of text (measured in tokens) a model can consider in one call.

The context window is the model's working memory — everything it can 'see' at once: your system prompt, the conversation history, any retrieved documents, and the response it's generating. Go over the limit and older content gets dropped or the call fails. Think of it as the size of the desk you can spread papers on: a big desk (say 200K tokens) fits a whole codebase, a small one fits a memo. In 2026, windows range from ~8K tokens to over a million.