Start writing free
The AI book editor for authors

Write the book Keep your voice

One quiet place for the whole book. It knows every chapter and source, and shows each change in red and green for you to keep or reject.

  • Free for one book
  • No credit card
  • Never used for training
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Launch film · 1:21Best with sound on
The editor

See how a book comes together.

Ten steps with one manuscript, from the first chapter to a book that is ready for print.

  1. 01 Book

    Your whole book in one place.

    Every chapter, front matter to back, open in one window.

  2. 02 Canon

    Your cast, remembered.

    Names in your pages become characters, places and the ties between them.

  3. 03 Sources

    Bring your research.

    Drop in a PDF or a link. It is read, indexed and ready to quote.

  4. 04 Goal

    Say what you want.

    Give the assistant a goal in plain words, the way you would brief an editor.

  5. 05 Work

    It reads before it writes.

    Your chapters, your cast and the new interviews, before a single line changes.

  6. 06 Review

    Red is cut. Green is new.

    Every change lands in your text in red and green. Keep or reject each one.

  7. 07 Accept

    Yes, yes, and yes.

    Accept one change at a time. Each one settles into ink, and the count goes down.

  8. 08 Citations

    Every claim has a source.

    Point at a citation and see the page it came from. The footnotes follow.

  9. 09 Preview

    See it typeset.

    One click turns the manuscript into the printed book: running heads, folios, drop caps.

  10. 10 Export

    Ready for the press.

    A print-ready PDF at your trim size, an EPUB, or Word for your editor.

Compared

Already using something else?

Chaptora compared with Sudowrite, Novelcrafter, Scrivener and Atticus
FeaturePricingCompareCompareCompareCompare
Chapters you can organise and reorder
AI writing help built inBring your own AI key
Story bible the AI reads (characters, places)
AI agent that carries one goal across many chaptersChat output pasted in by handNo built-in AINo built-in AI
Every AI edit shown in red and green to keep or rejectDiff in Quick Edit onlyApply or Discard, no diffNo built-in AINo built-in AI
AI that reads your own research (PDFs, web pages)Text documents onlyNotes typed into the CodexKeeps research files; no AINo built-in AI
AI answers that name the sources they usedNo built-in AINo built-in AI
Footnote citations and a generated bibliographyFootnotes; bibliography via other appsFootnotes; bibliography typed by hand
Word (DOCX) export
EPUB ebook export
Print-ready PDF for self-publishing
Preview of the typeset book before you export
Free plan, not only a trialFree trial21-day trial30-day trial30-day refund
Feature
Chapters you can organise and reorder
AI writing help built in
Story bible the AI reads (characters, places)
AI agent that carries one goal across many chapters
Every AI edit shown in red and green to keep or rejectDiff in Quick Edit only
AI that reads your own research (PDFs, web pages)Text documents only
AI answers that name the sources they used
Footnote citations and a generated bibliography
Word (DOCX) export
EPUB ebook export
Print-ready PDF for self-publishing
Preview of the typeset book before you export
Free plan, not only a trialFree trial
Chaptora vs Sudowrite, in full

Sources checked 8 November 2026, on each tool’s own pages.

Compare all book writing tools
Pricing

Start free. Grow when the book does.

Every plan
  • The agent
  • Word manuscript import
  • Front and back matter editor
  • Citations from your sources

Octavo

$0forever$0forever

Try it on one book, free

  • 1 book
  • Base monthly AI usage
  • 3 research files, up to 5 MB each
  • 3 saved versions
  • PDF export with a Chaptora cover page
Start writing free

Folio

$100per month$83.33per month · billed $1,000/yr

For heavy research and daily agent work

  • Unlimited books
  • 50× Octavo’s monthly AI usage
  • Unlimited research files, up to 200 MB each
  • Unlimited saved versions
  • Clean PDF, EPUB and Word export
  • Web research: 10 searches, 20 pages per message
Choose Folio

Prices in USD, excl. VAT.

Compare every limit side by side

Questions

What authors ask first.

Yes, if you want it to.

Chaptora can draft whole chapters from your outline, sources and voice sample, or work beside you on a single passage, a tighter paragraph or a fact check. Every change lands in your text in red and green, and you keep or reject each one. How much you hand over is up to you.

It works from a page of your own prose and your writing rules, and it avoids machine-text habits such as stated feelings and tidy closing summaries.

Paste a voice sample once and Chaptora follows its rhythm and sentence shape. Where your style breaks a rule on purpose, your style wins. New prose stays in the language of your chapters.

Never.

Your chapters and sources are used only to answer you, never to train any model, and never shared. The book lives in your Chaptora account, saved as you type, with your uploads stored privately beside it. Export a copy whenever you like; deleting the book deletes everything in it.

Yes.

Import a Word manuscript or pasted text and Chaptora splits it into chapters. You check titles, order and the split before anything is created. Paragraphs, headings, bold, italic, lists and images come along. Import works on every plan, uses none of your AI allowance, and the uploaded file is discarded afterwards.

Chaptora handles both.

Novels get characters, places and a timeline in a canon that a scan checks for contradictions. Non-fiction gets uploaded research, footnote citations, a Chicago bibliography and answers that name the sources they used. Print layout and export work the same for both, and you can write in any language.

One book, three research files, monthly AI usage and PDF export with a Chaptora cover page.

Octavo is free with no credit card and includes the agent; research files can be up to 5 MB each, with three saved versions. Quarto and Folio add unlimited books, EPUB and Word export and more usage. The pricing page lists every limit.

Finish the book, not the setup.

Start writing free
  • Free for one book
  • No credit card
  • Never used for training