AI Context Window Calculator — Free Online Tool
Paste your prompt and instantly see token estimates, context window usage, and cost breakdowns for 14 popular LLM models.
Check if your prompt fits GPT-4, Claude, Gemini context windows. Estimate tokens, usage %, and API costs per model.
| Model | Context | Max Out | Your Usage | Fits? |
|---|---|---|---|---|
| GPT-4o | 128.0K | 16.4K | 0.0% | — |
| GPT-4o mini | 128.0K | 16.4K | 0.0% | — |
| GPT-4 Turbo | 128.0K | 4.1K | 0.0% | — |
| GPT-3.5 Turbo | 16.4K | 4.1K | 0.0% | — |
| Claude 3.5 Sonnet | 200.0K | 8.2K | 0.0% | — |
| Claude 3 Opus | 200.0K | 4.1K | 0.0% | — |
| Claude 3 Haiku | 200.0K | 4.1K | 0.0% | — |
| Gemini 1.5 Pro | 2.1M | 8.2K | 0.0% | — |
| Gemini 1.5 Flash | 1.0M | 8.2K | 0.0% | — |
| Llama 3.1 405B | 128.0K | 4.1K | 0.0% | — |
| Llama 3.1 70B | 128.0K | 4.1K | 0.0% | — |
| Mistral Large | 128.0K | 4.1K | 0.0% | — |
| DeepSeek V3 | 128.0K | 8.2K | 0.0% | — |
| Cohere Command R+ | 128.0K | 4.1K | 0.0% | — |
Token estimates are approximate (~4 chars/token for English, ~3.2 for code). For exact counts, use the official tokenizer for your model.
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Paste your prompt and instantly see token estimates, context window usage, and cost breakdowns for 14 popular LLM models.
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