Context Window
Also: context length, token limit
The context window is how much text Claude can hold in its attention at once — your conversation history, any documents you've shared, system instructions, and Claude's own responses. Once you hit the limit, older content gets pushed out. Claude 3.7 Sonnet has a 200,000-token context window, which is roughly 150,000 words. Long contexts let Claude analyse full documents or maintain long conversations — but they also cost more and can sometimes cause Claude to lose focus on earlier material.
Articles
The whiteboard every AI conversation shares
Context window is the single number that shapes everything about how Claude thinks with you — and most people are using only a fraction of it.
How to think about Claude's context window (and when it actually matters)
200,000 tokens sounds enormous. In practice, how you use that space changes everything about the quality of your outputs.
The context window in practice: what it means for how you work
The context window is not just a technical spec — it shapes what Claude can and can't do in any given conversation. Here is how to work with it.