How to Use the LLM Prompt Token Counter & Cost Estimator
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Paste your prompt or document text.
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View estimated tokens based on BPE (Byte-Pair Encoding) heuristics.
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Compare estimated API invocation costs across leading AI models.
Practical Example & Use Case
Common Real-World Scenario
Checking if a 12,000-word product specification fits into a 16k context window and calculating the inference cost.
Technical Notes & Limitations
Browser Engine Architecture
Estimates are based on calibrated cl100k/o200k BPE tokenizer statistics (approx. 4 chars per token for English). Exact token counts may vary by ±3%.
Frequently Asked Questions
How many characters is one token?
In English, 1 token is roughly 4 characters or 0.75 words on average. Code and non-Latin scripts typically use more tokens per word.
Does this send my prompt to any server?
No. The entire calculation runs locally in your browser with zero network requests.