How does Claude handle very long documents compared to other AI tools?

Claude has one of the largest context windows of any commercial AI model — up to 200,000 tokens, which is roughly 150,000 words or about 500 pages of text. This means you can paste or upload an entire book, a full legal agreement, or a large codebase and Claude will read and reason across all of it in a single session. ChatGPT with GPT-4o supports up to 128,000 tokens which is also large, but Claude's edge is in how well it actually uses that context — it tends to stay accurate and consistent even when referencing details from early in a very long document, which some other models struggle with.