Part of the AI writing assistant guide

AIWriteBook vs ProWritingAid: which one fits the book you are working on?

ProWritingAid is an editing coach. It reads your prose, flags what to fix and explains why, and it promises it will never write the book for you. AIWriteBook does the opposite job too: it helps you write the chapters, then edits, formats and publishes them. Which one you need depends on where your book is right now, so this page walks through four real situations instead of a feature list. For the wider picture, see our guide to AI writing assistants.

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Four authors, four different answers

Same question, different books. Here is how each tool handles the situation and which one we would pick.

Scenario 1

You finished a 90,000-word thriller and need a line edit before beta readers see it

With ProWritingAid

This is what ProWritingAid was built for. Paste or open the chapters and run its grammar check, Rephrase and the 25+ writing reports on Premium: overused words, sticky sentences, pacing, dialogue tags. Premium adds one Chapter Critique a day, and Manuscript Analysis reads the whole story up to 300,000 words. That analysis is paid for with Story Credits, sold on top of the subscription.

With AIWriteBook

Import the .docx (up to 200,000 words) and your text comes in unchanged, split into chapters you can rename or reorder. The Book Editor then writes an editorial letter and a style sheet for the whole book, line-edits each chapter and runs a proofread pass. Every replacement shows up as a change you accept, reject or skip, and accepted changes land straight in the manuscript.

Either works

Both do the job. ProWritingAid is better if you want to learn why a sentence is weak. AIWriteBook is better if you want the fixes applied in a manuscript you will format and publish in the same place.

Scenario 2

You have a premise for a fantasy trilogy and an empty document

With ProWritingAid

ProWritingAid can help you think. Story Canvas gives feedback on your idea, Premium adds the Outline Crafter, and Sparks and Creative Nudges offer prompts when you stall. The prose is yours to write: its site says plainly that it will never write the book for you.

With AIWriteBook

Describe the book and you get an editable chapter outline and a cast of characters for free. Paste six to ten paragraphs of your own writing on the Writing Style step and each chapter is drafted from the outline in that voice, then refined in the chapter chat, where each edit arrives as a diff. When book one is done, book two can read up to 5 previous books so names and timelines carry over.

Pick AIWriteBook

AIWriteBook. If the problem is getting 300 pages onto the page, a critique tool has nothing to critique yet.

Scenario 3

You draft in Word, Scrivener or Google Docs and do not want to change apps

With ProWritingAid

ProWritingAid lists integrations with MS Word, Google Docs, Scrivener, Apple Pages, Atticus, a desktop editor and browser extensions for Chrome, Firefox and Edge. The suggestions appear where you already write.

With AIWriteBook

AIWriteBook is its own web app. You can bring a .docx in and take a DOCX back out, but the writing and editing happen in our editor, not inside Word or Scrivener.

Pick ProWritingAid

ProWritingAid. If your workflow is settled and you only want a second pair of eyes inside it, that is the tool to keep.

Scenario 4

The edit is done and you want the book live on Amazon KDP

With ProWritingAid

ProWritingAid stops at the words. Its plans list editing reports, critiques and community workshops, not ebook or print file export, so the formatting, cover and listing happen in other tools.

With AIWriteBook

One Generate in the Format step builds a print PDF, an EPUB, a wrap cover sized for KDP and IngramSpark, and a DOCX. You can design the cover, generate KDP keywords and a description (try the free KDP keyword tool first), and turn the finished text into an audiobook with 25 voices.

Pick AIWriteBook

AIWriteBook. The book is maybe forty percent of the job, and this is the other sixty.

The short version

What mattersProWritingAidAIWriteBook
Main jobEditing and critique of text you wroteWriting, editing, formatting and publishing a whole book
Writes chapters for youNo, by designYes, from your outline and in your writing style, or you write them yourself
Grammar and style checksGrammar, spelling, Rephrase and 25+ writing reportsProofreader, grammar and style check, line edits with accept or reject
Whole-book feedbackManuscript Analysis via Story Credits, up to 300,000 wordsEditorial letter and style sheet from the Book Editor
Works inside other appsWord, Google Docs, Scrivener, Atticus, browser extensionsWeb app with .docx import and DOCX export
Series memoryNot listedReads up to 5 previous books
Publishing filesNot listed on its plansPrint PDF, EPUB, wrap cover and DOCX
AudiobookNot listedWhole-book audiobook with 25 voices

ProWritingAid details from prowritingaid.com and its pricing page, October 2026.

What each one costs

ProWritingAid sells a subscription to its editing tools, with whole-manuscript analysis paid separately. AIWriteBook charges credits for what the AI writes and edits, with the planning stage free.

ProWritingAid

  • Free$0Suggestions on 500 words at a time, 10 Rephrases and 3 Sparks a day
  • Premium$30/moOr $120 a year, or $399 once for lifetime access
  • Premium Pro$36/moOr $144 a year, or $699 once. Adds more critiques and live workshops
  • Manuscript AnalysisStory CreditsBought separately, discounted on paid plans

AIWriteBook

  • Free$0Outline, characters and your first chapter
  • Plansfrom $12/moBilled yearly
  • Credit packsfrom $20$20 for 250 credits or $50 for 2,000 credits, no subscription

If you only need line editing on a book you already wrote, a ProWritingAid yearly plan is cheap and thorough. If you also need the chapters drafted, a cover and KDP files, compare that with what a separate editor, formatter and cover designer would cost; our self-editing guide breaks down which steps are worth paying a human for.

Where ProWritingAid is better

We would rather you pick the right tool than the wrong one.

  • It explains its suggestions, so you become a better self-editor over time.
  • It lives inside Word, Google Docs, Scrivener and your browser.
  • The writing reports go deep on style: sticky sentences, overused words, sentence variety, dialogue tags.
  • A lifetime license is available, and Premium Pro includes live workshops with authors and editors.

Who should stay

Stay with ProWritingAid if your draft is finished, you enjoy editing it yourself and you never want an AI to write a sentence for you. You can still run our free grammar checker on a chapter to compare.

Keep reading

ProWritingAid questions authors ask

Is AIWriteBook a good ProWritingAid alternative?

It depends on the job. For pure line editing and learning to self-edit, ProWritingAid is excellent. If you want help writing the chapters, plus editing, formatting, a cover and publishing files in one place, AIWriteBook covers more of the book.

Does ProWritingAid write books for you?

No. ProWritingAid says it will never write it for you. Its AI features critique, rephrase and prompt, but the prose is yours. AIWriteBook can draft chapters from your outline in your own writing style, or you can write them yourself and use only the editing tools.

Can I edit a novel I already wrote in AIWriteBook?

Yes. Import a .docx up to 200,000 words. The text is kept exactly as you wrote it, and the Book Editor gives you an editorial letter, line edits and a proofread pass that you accept or reject one change at a time.

How does pricing compare?

ProWritingAid Premium is $30 a month or $120 a year, Premium Pro is $36 a month or $144 a year, and Manuscript Analysis is paid for with Story Credits on top. AIWriteBook is free to start with your outline and first chapter, plans start at $12/mo billed yearly, and one-time packs start at $20.

Can I use both?

Yes, and some authors do. Draft and format in AIWriteBook, export a DOCX, and run it through ProWritingAid inside Word if you like its reports. Then import the cleaned file back to build the publishing files.

Will an AI-written chapter sound like me?

That is what the Writing Style step is for. Paste six to ten paragraphs of your own prose, or import a manuscript and the style is learned from it, and every chapter is drafted with that sample as the reference. You still read and change every line, and the chapter chat shows each edit as a diff before it lands.

Have the idea but not the draft? Start there, free

Outline, characters and chapter one cost nothing. Edit and publish when you are ready.

Free to start, no credit card
  • Outline and first chapter free
  • Print PDF, EPUB, wrap cover and DOCX from one Generate
  • 25 audiobook voices
  • Write in 37 languages
  • One-time credit packs from $20, no subscription
Your first chapter is free