Context Window Visualizer

Paste your system prompt and user message to see how much context you're using across models.

Instructions given to the AI — defines its role and behavior

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The actual prompt or question the user sends to the AI

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Total Input

0

tokens

Context Usage by Model

claude-opus-4-6

Anthropic

1M context

0.0% used1M remaining

gpt-5.4

OpenAI

1.1M context

0.0% used1.1M remaining

gemini-3.1-pro-preview

Google

1.0M context

0.0% used1.0M remaining

claude-sonnet-4-6

Anthropic

200K context

0.0% used200K remaining

gpt-5

OpenAI

272K context

0.0% used272K remaining

gemini-3.1-flash-lite-preview

Google

1.0M context

0.0% used1.0M remaining

deepseek-chat

DeepSeek

131.1K context

0.0% used131.1K remaining

deepseek-reasoner

DeepSeek

131.1K context

0.0% used131.1K remaining

qwen-max

Alibaba (DashScope)

30.7K context

0.0% used30.7K remaining

o4-mini

OpenAI

200K context

0.0% used200K remaining
System prompt
User message
Available