SynaBot

What is a context window?

The context window is the maximum amount of text the model can hold in its "working memory" at once — prompt, uploaded files, and its own reply included.

Mark Barclay
Answer curated and reviewed byMark Barclay

Key takeaways

  • The context window is the maximum amount of text the model can hold in its "working memory" at once.
  • prompt, uploaded files, and its own reply included.

Every conversation is bounded by a context window (measured in tokens). Once you exceed it, earlier parts of the conversation get dropped or summarized, and the model starts to lose the plot.

Today's frontier models offer 200k–1M+ token windows — enough to hold a book. Older or cheaper models are much smaller. If long documents are your use case, pick a model with a big window.