maratoolAI Context Window Calculator
Paste text and select a model to see token count, context window usage, and remaining capacity.
0Tokens used
—Context limit
0%Usage
—Remaining
How to use
- Select the AI model to check against.
- Paste your prompt or text.
- See token count, usage percentage, and remaining context.
Frequently asked questions
How are tokens estimated?
Approximately 4 characters per token for English text — same heuristic as our AI token counter.
What happens if I exceed the context window?
The API will reject the request or truncate input. Stay under 80% for safety margin.
Are context limits accurate?
Limits reflect published model specs. Providers may update limits — verify on official docs.
Is my text sent to a server?
No. Token estimation happens entirely in your browser.
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