AI Context Window Visualizer

800 tok
8,000 tok
200 tok
2,000 tok
080%95%1,000,000 tokens
Total Allocated
11,000
1.1% of context
Remaining
989,000
Est. Turns Left
~1978
at 500 tok/turn
Cost (full context)
$0.0275
input only
Status
Healthy
Good balance

About Context Window Visualizer

Visualize how your LLM context window is allocated across system prompts, tools, conversation history, RAG chunks, and response budget. Yellow warning at 80% usage, red critical at 95%.

Cost estimates are based on published API pricing. Token counts from pasted text use a ~4 chars/token approximation. For precise counts, use the Token Counter tool.

What This Tool Does

AI Context Window Visualizer is built for deterministic developer and agent workflows.

Visualize how your AI model's context window is allocated across system prompt, tools, conversation, and RAG.

Use How to Use for execution steps and FAQ for constraints, policies, and edge cases.

Last updated:

This tool is provided as-is for convenience. Output should be verified before use in any production or critical context.

Agent Invocation

Best Path For Builders

Browser workflow

Runs instantly in the browser with private local processing and copy/export-ready output.

Browser Workflow

This tool is optimized for instant in-browser execution with local data handling. Run it here and copy/export the output directly.

/context-window-visualizer/

For automation planning, fetch the canonical contract at /api/tool/context-window-visualizer.json.

How to Use AI Context Window Visualizer

  1. 1

    Enter your model's context window

    Input the model name (e.g., 'GPT') and its total context window (e.g., 128,000 tokens). The visualizer shows how the available context is allocated.

  2. 2

    Add system prompt

    Paste your system prompt. The visualizer calculates tokens and shows how many tokens it consumes. Account for this when planning conversation length.

  3. 3

    Estimate conversation length

    Input expected number of messages in the conversation, average tokens per user message, and average tokens per assistant response. The tool shows total conversation tokens and remaining context.

  4. 4

    Plan for output

    Reserve tokens for the expected response (e.g., 1000-2000 for longer outputs). The visualizer shows the remaining context available. If it gets tight, reduce history or truncate earlier messages.

Frequently Asked Questions

What is a context window in AI models?
The context window is the maximum number of tokens a model can process in a single request. It includes everything: system prompt, tool definitions, conversation history, retrieved context, the user query, and the model's response.
How is this different from Token Budget Planner?
Token Budget Planner focuses on planning system prompt sections. Context Window Visualizer shows the FULL allocation including conversation turns, tool definitions, RAG chunks, and response budget — giving you a complete picture of context usage.
Why do I run out of context window?
Tool definitions, long system prompts, and conversation history accumulate over turns. Each tool definition can consume 200-500 tokens. This visualizer shows exactly what's consuming your context so you can optimize.
Which AI model has the largest context window?
Context windows vary by provider and model tier. This tool shows context capacity for major model families and helps you compare them side by side using current data.
Does this tool make API calls?
No. All calculations happen in your browser. Model data is pre-loaded. No API keys or internet connection required for calculations.