Best AI for Writing a Book in 2027: Five Ways Compared

What is the best AI for writing a book? Two questions decide it: what kind of book, and who should write the text. For novels, there are tools built around stories and characters: Sudowrite, Novelcrafter and Squibler, all on monthly or yearly plans. For a non-fiction or self-help book written from your idea, Bookfairy plans the book like a publisher, writes every chapter and takes the manuscript on to the full cover, formatting and EPUB, once per book from $58.80490 tokens. A general AI chat writes good pages, but not a finished book. Below are the five ways with what each produces and how you pay, as of November 2026.

This guide is about choosing a tool. How to write and publish an AI book step by step, and what Amazon KDP's AI rules say, is in our guide Writing a book with AI.

What an AI has to do to write a whole book

A book is not a long chat reply. Whatever tool you pick, check it against these five jobs:

Research explains why long texts are hard for language models: they use information at the start and end of a long input much better than in the middle (Liu et al., 2023), and training rewards guessing over admitting uncertainty (Kalai et al., 2025). Tools that plan the whole book first and write along that plan work around both.

Five ways at a glance

Prices from each provider's own site, US prices in USD, checked November 8, 2026.

For fiction: Sudowrite, Squibler and Novelcrafter

• Sudowrite describes its own models as "AI models just for fiction", and its AI Book Writer supports all fiction genres. From your novel idea it builds 10 detailed chapter outlines and 2 to 3 character arcs; you then expand each chapter, 5,000 to 10,000 words, in the editor. Each plan comes with a monthly credit allowance, and the free trial needs no credit card.
• Squibler calls itself an AI story writer for books, novels and screenplays. From the Plus plan it generates a full 200 to 300 page book, keeps characters, plot and structure consistent and exports to PDF and DOCX. The free plan includes 500 AI credits a month; billed annually, Plus costs $15.83 instead of $29.99 a month.
• Novelcrafter is a planning and writing environment: a codex, series and, from the Hobbyist plan, AI features that run on your own key with an AI provider, which you pay separately. There is a 21-day trial and no free plan; after cancelling you keep read-only access and can export your data.

Each of the three has its own page next to Bookfairy: Sudowrite vs. Bookfairy, Squibler vs. Bookfairy and Novelcrafter vs. Bookfairy.

For non-fiction and self-help: Bookfairy

Bookfairy is made for non-fiction and self-help. It does not write novels or children's books. Instead of an editor that waits for your next prompt, it writes the book itself:

1. Describe your idea. Topic, readers and tone in a few sentences, typed or spoken. Notes or a table of contents help, but you do not need them.
2. Read the concept and chapter 1 for free. You get the brief a publisher would write (who the book is for, what it promises, how it is built), an outline with a summary per chapter and the complete first chapter. Change the structure until it is your book.
3. Unlock the whole book. Every chapter is written in turn along the outline, in English, German, French, Spanish or Italian. You get a Word file with chapters, table of contents, checklists, tables and a list of sources.
4. Carry on in the same project. Editing checks spelling, grammar, style, logic and facts with every change marked, the cover comes with front, spine and back as a print PDF, with the barcode and publisher logo on the back, and formatting, EPUB, blurb, keywords and categories take it from there. The cover workshop later translates the cover, same look in the other language ($4.8040 tokens), changes the trim size or page count ($2.4020 tokens), makes an audiobook cover ($2.4020 tokens), swaps barcode or logo ($1.2010 tokens) or changes it in your own words ($1.2010 tokens per change).

The AI book writer costs $58.80490 tokens up to 30,000 words, $82.80690 tokens up to 60,000 and $106.80890 tokens up to 100,000, once per book. Optionally, name up to three bestsellers in your genre: Bookfairy reads their public details, learns what readers love and miss, and builds an original concept for your book. Model books only guide style and market fit. Your result is your own original work.

A general AI chat: good pages, no finished book

A chat answers in replies. For 60,000 words you send dozens of requests and keep the plan together yourself. Typical results: a rule called "five minutes" in chapter 2 and "three minutes" in chapter 9, the same anecdote in chapters 4 and 11, and studies that do not exist. When the text is done, the print PDF, the cover with spine, plus barcode and publisher logo on the back, the EPUB, the blurb and the keywords are all still to do.

Which AI for which book?

Whichever tool writes the draft, read and revise it before you publish. Your own revisions make the book yours and strengthen your rights in the text. Writing apps where you type every word yourself, such as Scrivener and Atticus, are compared in our guide Best book writing software.