1,000 English Words Equal ~1,300 LLM Tokens: A Quick Conversion Guide

A practical reference guide explains that 1,000 words of standard English prose converts to approximately 1,300 tokens, while 1,000 tokens translate back to roughly 750 words or 4,000 characters. These ratios hold for plain English but break down significantly for code, JSON, URLs, and non-Latin scripts like Arabic, Chinese, and Japanese, which can consume several tokens per character. Different AI models use different tokenizers, meaning token counts are not universal and estimates should not be relied upon for hard limits or billing calculations. For precise counts, OpenAI's tiktoken library and token-counting API endpoints from Anthropic and Google are recommended. The guide also warns that context windows must accommodate system prompts, conversation history, retrieved content, and model output together, making early token estimation a useful habit before inserting large documents into prompts.