AI Glossary
What is Context Window?
The maximum amount of text, measured in tokens, that an AI model can consider at one time, including your messages, uploaded documents and its own replies in the conversation.
Think of the context window as the AI's working memory for one conversation. Everything inside it (your earlier messages, pasted documents and the AI's answers) can influence the next reply. Anything beyond it is not seen.
Context windows have grown a lot, and many assistants can now handle long documents. But limits still exist, and they vary by tool and plan.
Signs you are hitting the limit:
- The AI "forgets" details you gave early in a long chat.
- It refuses or truncates very large uploads.
- Answers start contradicting what was agreed earlier.
What to do:
- Start a new chat for each new task.
- Paste only the relevant part of a long document.
- In a long chat, ask the AI to summarise what has been agreed, then continue in a fresh chat with that summary.
Related: Token.