The context window is the maximum amount of text ChatGPT can process in a single conversation — both what you send and what it responds with.
Key Points
- GPT-3.5 — ~4,000 tokens (~3,000 words)
- GPT-4 — up to 128,000 tokens in some versions
- Once the window is exceeded, older parts of the conversation are forgotten
- ChatGPT has no memory between separate conversations by default
Think of it as short-term working memory, not long-term storage.
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