Paste your prompt or document. See exactly how it fits within each model's context window — with visual bars, remaining capacity, and cost at full context.
A context window is the maximum number of tokens an AI model can process in a single API call. This includes your input (prompt, system message, documents) AND the model's output (response). If your total exceeds the limit, the request fails.
max_tokens to limit output lengthCompare pricing, performance, and context windows across all 67 AI models.
Open Cost Calculator →Save context window scenarios, compare models side by side, and get cost optimization recommendations — all free.
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