Comparison

kdpbook.io vs AIWriteBook: an honest comparison

AIWriteBook is an AI book-writing app: it drafts chapter by chapter in your voice, edits, narrates audiobooks and, on Pro ($30/month billed yearly, $50 monthly), formats a PDF/X-1a print interior, a wrap cover and an EPUB for 200 credits per book. kdpbook.io plans and writes the whole book from one chat for 36 book types, or lays out your manuscript in 20 of them, and every paid plan from $25/month exports the interior PDF, the full-wrap cover and, for types that suit Kindle, an EPUB.

By kdpbook.io editorialPublished October 20, 2026

We make kdpbook.io, so we’re not neutral. Everything about AIWriteBook below comes from its public pages as of October 20, 2026 (each row links its source); prices and features may have changed since. Spot an error? Write to contact@thevibecodingagency.fr.

At a glance

kdpbook.io compared with AIWriteBook
Criterion	kdpbook.io	AIWriteBook
Main job	Writes and illustrates the book, or lays out your own manuscript, then builds the KDP files	Helps you write a book in your voice, then edits, formats, narrates and lists it source: AIWriteBook page for “Main job” (opens in a new tab)
Writing the book	Plans and writes the whole book from one chat (a novel runs 55,000–120,000 words), or imports your manuscript	Chapter by chapter from your outline, matched to 6 to 10 paragraphs of your own writing; you pick Gemini, Claude or Grok for each chapter source: AIWriteBook page for “Writing the book” (opens in a new tab)
Your own manuscript	Import a .docx, .doc, .pdf, .txt or .md file (or paste the text) for 20 of the 36 book types; your words are laid out as written, never rewritten	Word .docx only, up to 200,000 words and 32 MB; your prose is kept as written, with chapters, images and footnotes in place source: AIWriteBook page for “Your own manuscript” (opens in a new tab)
Output	Interior PDF, full-wrap cover PDF, Kindle EPUB + Kindle cover, and a KDP listing sheet	DOCX on Plus; on Pro, its Format step makes a PDF/X-1a print interior, a wrap cover, a validated EPUB and a DOCX (free accounts get a watermarked standard PDF) source: AIWriteBook page for “Output” (opens in a new tab)
Print interior	Trim, bleed, margins, spine and page limits applied automatically, with a preflight check	PDF/X-1a:2001 with every font embedded, 17 trims from 5 × 8 to 8.5 × 11 in with bleed and gutter set, and a preflight check; 200 credits once per book source: AIWriteBook page for “Print interior” (opens in a new tab)
Hardcover	5 hardcover trims	Not documented source: AIWriteBook page for “Hardcover” (opens in a new tab)
Cover	Full-wrap cover PDF sized from trim, paper and final page count	Front, spine and back as one file, the spine from the final page count and paper, with a reserved barcode zone (formatter, Pro) source: AIWriteBook page for “Cover” (opens in a new tab)
Kindle eBook	Kindle EPUB (reflowable or fixed layout) + Kindle cover	Validated EPUB from the formatter (Pro), and its Visual Books page says illustrated books export to print and EPUB too; whether either EPUB is fixed layout is not documented source: AIWriteBook page for “Kindle eBook” (opens in a new tab)
Illustrated books	61 illustration styles or your own; character reference sheets reused on every illustration	Visual Books on Pro and Ultra: picture books, comics, manga and coloring books, a reference image per character, text lettered on the page, 20 credits a page source: AIWriteBook page for “Illustrated books” (opens in a new tab)
Browser extension	On a paid plan, kdpbook Publisher, the free kdpbook.io extension for Chrome or Edge on a computer, fills your Amazon KDP draft from your export (details, categories, files and prices); you review it and click Publish yourself.	KDP Publishing Assistant for Chrome, Edge and other Chromium browsers: fills KDP's fields from your book (title, author, blurb, keywords, categories…) and checks each one as you type, free on any account; category research gets one free run, then needs Pro at 100 credits a run; you press Publish source: AIWriteBook page for “Browser extension” (opens in a new tab)
Audiobook	Not offered	Audiobook Studio: a narrator and a proposed voice for each character, exported as MP3 or M4B with chapter markers source: AIWriteBook page for “Audiobook” (opens in a new tab)
Languages	34 KDP-supported languages	Writes in 38 languages, per its pricing page source: AIWriteBook page for “Languages” (opens in a new tab)
Pricing	Free: 2,000 credits once, no card. Plans $25–$99/month	Free; $12–$120/month billed yearly, $20–$200 monthly; the formatter is on Pro ($30 or $50) source: AIWriteBook page for “Pricing” (opens in a new tab)

What AIWriteBook is

A web app to write, edit, format and distribute books. Builders for the characters, the outline and your writing style (from a sample of your prose) lead to chapters written one at a time, in 38 languages, with Gemini, Claude or Grok; a Word draft can be imported instead. On Pro, a Book Editor scores the manuscript and line-edits it, the Format step typesets the print interior, wrap cover, EPUB and DOCX, Visual Books makes picture books, comics, manga and coloring books, and an Audiobook Studio narrates the text. A free Chrome extension fills KDP's setup pages from the book.

Where it shines

Chapters written to a sample of your own prose, with the model picked per chapter (Gemini, Claude or Grok), and a Book Editor that scores the book on 30 criteria for its genre, writes an editorial letter and proposes line edits you accept or reject.
A formatter for several stores: PDF/X-1a print files for Amazon KDP, IngramSpark, Lulu, Draft2Digital with Barnes & Noble Press and BookVault, plus an EPUB and a DOCX, re-generated free after the 200-credit unlock.
Visual Books for picture books, comics, manga and coloring books, with a reference image for every character; the first two illustrated pages of a first visual book are free.
An Audiobook Studio with a narrator and a voice for each character, and a free KDP extension that fills and checks KDP's setup pages while you press Publish.
Its terms leave you full ownership and commercial rights to what you create.

AIWriteBook pricing

Free: 100 credits (about 12 pages) for the character, outline and writing-style builders, manuscript import and a first chapter.
Plus $12/month billed yearly or $20 monthly (1,000 credits a month): chapter writer, Cover Maker, the KDP Publishing Assistant (its extension page says the checks and fill are free on any account) and DOCX export. Pro $30 or $50 (5,000 credits): adds the formatter, Visual Books, the Audiobook Studio, translation and the Book Editor. Ultra $120 or $200 (25,000 credits, bring your own API key).
Formatting costs 200 credits once per book (Pro, Ultra and its AppSumo tiers), then re-generates free. Writing a chapter costs 15 to 30 credits depending on the model; an illustrated page, 20.
One-time packs of 250 credits ($20) or 2,000 credits ($50) unlock the Plus features and expire 3 months after purchase.
Its terms (updated October 20, 2026) refund a first subscription within 7 days if less than half its credits were used; renewals and delivered credit packs aren't refundable.

As published on October 20, 2026. See the current prices on its website.

Which one should you choose?

Choose AIWriteBook if…

You want to write the book yourself, chapter by chapter in your own voice, with an editorial letter and line edits you approve one by one.
You want an audiobook with character voices from the same manuscript.
You publish beyond Amazon too: its print files are made for IngramSpark, Lulu, Draft2Digital and BookVault as well as KDP.

Choose kdpbook.io if…

You want the whole book planned and written from one chat, or laid out from your manuscript in a .docx, .doc, .pdf, .txt or .md file (20 of the 36 book types take an import).
Your book needs a hardcover edition (5 trims) or a fixed-layout Kindle edition for a picture book or a comic.
You make puzzle books whose 7 kinds of puzzle are generated and checked by code, with solutions, or guided journals.
You want the print and Kindle files on every paid plan, from $25/month, with layout counted in the book's estimate (plan, layout, cover art) shown before you launch.

Questions

Is kdpbook.io an AIWriteBook alternative?

For many KDP books, yes. Both write with AI, keep illustrated characters consistent with a reference per character, export a print PDF, a wrap cover and an EPUB, and have a browser extension that fills KDP's pages while you click Publish yourself (kdpbook.io's on paid plans). AIWriteBook is built around writing in your own voice chapter by chapter, with an AI editor and audiobooks. kdpbook.io plans and writes the whole book from one chat across 36 book types, or lays out your manuscript in 20 of them; a 336-page novel (about 80,000 words) is estimated at about 5,377 credits (≈ $54), interior, cover and Kindle file included.

Which AIWriteBook plan includes the formatter?

Pro ($30/month billed yearly, $50 monthly), Ultra and its AppSumo lifetime tiers, for 200 credits once per book; Plus ($12 or $20) keeps the DOCX export, and free accounts get a watermarked standard PDF, as published on October 20, 2026. On kdpbook.io every paid plan, from $25/month, exports the interior PDF, the full-wrap cover and, for book types that suit Kindle, an EPUB; free-plan files carry a preview watermark.

Can I lay out an AIWriteBook manuscript with kdpbook.io?

Yes. Export it from AIWriteBook as a DOCX (Plus and up) and import it into a novel or another text book type: 20 of the 36 types accept an import, and words, punctuation and line breaks inside paragraphs are kept. Reading the manuscript costs 3 credits per 1,000 words, and the book's estimate (plan, layout, cover art) is shown before you launch.

Sources · read on October 20, 2026

We re-read every comparison at least every 90 days. Spot an error? Write to contact@thevibecodingagency.fr.

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