Question: Is there a tool that can correct grammar in large documents, like entire books, at once?

If you need a tool to fix grammar in documents like books, BulkCorrector is a powerful option. It can split text into smaller blocks so you can make bulk corrections and translations. BulkCorrector's free tier is good for casual writers and its premium tier for heavier use, and it's designed to work on documents of any size.

Another good option is LanguageTool, which offers a broad grammar check and paraphrasing ability across more than 30 languages. It's designed to work with many writing tools and offers a free version and a premium version. Premium features include a more advanced grammar and punctuation check, so it's good for serious writers and students.

Grammarly is another option worth considering, especially if you want writing advice that's tuned to your style and that works in many apps. It offers contextual advice, plagiarism detection and citation support, so it's good for anyone who wants to write more efficiently and accurately. Grammarly offers a range of plans from free to enterprise.

If you're an academic or technical writer, Trinka offers a more sophisticated grammar and style check, along with a plagiarism detector and a proofreader for MS Word documents. Trinka is designed to make your life easier with tools like a consistency check and a citation checker, so it's good for anyone who wants to dig deeper into their writing and get more feedback.