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Claude Token Counter
Estimate prompt token consumption for Anthropic Claude 3.5 Sonnet, 3.7, and Claude Opus models. Manage your 200k context window accurately.
Estimated Tokens
0
for Claude 3.5 / 3.7 Word Count
0
Whitespace separated Characters
0
0 no spaces Tokens / Word
0.00
Density index Active Model Tokenizer:
Tokenizer: Anthropic
Why token count matters more than word count
Context windows and API quotas are strictly bounded by tokens. When optimizing system prompts or stuffing retrieved context into LLM calls, managing your token envelope is the primary lever for cost and latency control.
Rule 1
~4 Characters / Token
In standard English prose, 1 token is roughly 4 characters or ~0.75 words.
Rule 2
Code is Denser
Code, symbols, and non-Latin characters generate significantly more tokens per character.
Rule 3
Trim Context First
Pasted files and retrieved documents make up 90% of token weight. Strip boilerplate first.