How Much Text Fits in 200k Tokens?

A 200,000 token context window fits approximately 150,000 words (roughly 300 single-spaced pages). This is enough to hold a complete 400-page book or about 20 large source code repositories. GPT-4o easily handles this capacity, whereas Claude Opus has this as a standard base window.

Context Window Capacity Calculator

Input Unit

Number of Words

Standard English Estimate: 200,000 tokens (actual counts vary by model tokenizer below)Approximate Characters: 800,000 characters

Context Window Consumption by Model

Visual representation of how much context window is consumed based on your input parameters.

Llama 4 Scout (17B)194,805 / 10,000,000 (1.95%)

Gemini 3.5 Flash200,000 / 1,048,576 (19.07%)

Claude Fable 5205,479 / 1,000,000 (20.55%)

Claude Sonnet 4.6205,479 / 1,000,000 (20.55%)

GPT-5.5192,308 / 1,050,000 (18.32%)

GPT-4oExceeded (150%)

GPT-4Exceeded (2409%)

o4-mini192,308 / 200,000 (96.15%)

Qwen 3.6 27B197,368 / 262,144 (75.29%)