Skip to content

Instantly share code, notes, and snippets.

@karthiks

karthiks/claude-session-context-window.md

Created March 21, 2026 07:56
Show Gist options

  • Select an option

    Learn more about clone URLs
  • Save karthiks/ddddd3f04215a9c270d7cc666c38cf6d to your computer and use it in GitHub Desktop.

Select an option

Learn more about clone URLs
Save karthiks/ddddd3f04215a9c270d7cc666c38cf6d to your computer and use it in GitHub Desktop.
Download ZIP
Session Context Window (200k total)
Raw
claude-session-context-window.md 
Session Context Window (200k total)
┌────────────────────────────────────────────┐
│ System Prompt + Tools: 15.9k (8%)          │ ← Fixed allocation
│ CLAUDE.md + Memory: 2.8k (1.4%)            │ ← Fixed allocation
├────────────────────────────────────────────┤
│ Messages (grows over time): 89.5k (44.7%)  │ ← This grows
├────────────────────────────────────────────┤
│ Free Space: 59k (29.5%)                    │ ← This shrinks
│ Autocompact Buffer: 33k (16.5%)            │ ← Reserved
└────────────────────────────────────────────┘
  • The data occupency percentage is for representational purpose. The key is to understand what is fixed,reserved, growing and shrinking.
  • The system prompt, tools, and CLAUDE.md occupy a fixed portion of your context window for the ENTIRE session. They don't "grow" or "lose" space with each message. Let me visualize.
  • The system components take up a fixed chunk at the start. What grows (and what you should worry about) is the Messages section, which accumulates your conversation history.
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment