AIWriteBook vs Wordtune: a sentence rewriter or a book writer?
Wordtune, made by AI21 Labs, is good at one thing: take the sentence you just typed and offer better versions of it, right where you type in your browser. AIWriteBook works at the size of a book, from outline to chapters to a cover and KDP files. Most authors asking for a Wordtune alternative have outgrown the sentence. Here is how to tell.
At a glance
| What matters | Wordtune | AIWriteBook |
|---|---|---|
| Unit of work | A sentence or paragraph | A whole book, chapter by chapter |
| Rewriting | Casual, formal, shorter or longer versions of your text | Chapter chat edits shown as a diff, accept or reject each change |
| Writing new text | Continues or expands what you wrote | Outline, characters and full chapters in your style |
| Where it works | Chrome and Edge extensions, an iOS app and its website | Web app built around the book |
| Writing languages | Writes in English, translates into English from 10 languages | Writes books in 37 languages, translates whole books |
| Publishing | Not offered | Print PDF, EPUB, wrap cover, DOCX, KDP metadata, audiobook |
| Price | Free with 10 rewrites a day; paid from $6.99/mo | Free outline and first chapter; plans from $12/mo |
Wordtune details from wordtune.com and its plans page, October 2026.
Three moments in a writer's week
Tap a scenario to see how each tool handles it.
MondayOne clunky paragraph in an email to your editorWordtune
You are writing to your editor in your browser and one paragraph sounds stiff.
Wordtune: Highlight it and Wordtune offers several rewrites right there, more formal or more casual, shorter or longer. It takes seconds and you never leave the page.
AIWriteBook: AIWriteBook is not built for email. For a quick one-off you could paste the paragraph into our free paraphrasing tool, but that is a detour.
Wordtune. Sentence-level polish wherever you type is exactly its job.
WednesdayTurning a 2-page premise into a 70,000-word novelAIWriteBook
You have a premise, three characters and a deadline you set for yourself.
Wordtune: Wordtune can continue a paragraph or expand a point, but it has no outline, no character list and no memory of chapter four when you reach chapter twenty.
AIWriteBook: The outline builder turns the premise into chapter plans and characters, free. Chapters are drafted from that plan in the writing style you provide, and the chapter chat rewrites any passage, with every change shown before you accept it.
AIWriteBook. A book needs a plan that holds across 70,000 words, not a better sentence.
FridayWriting the book in German, then selling it in English tooAIWriteBook
Your readers are in Germany, but you also want an English edition.
Wordtune: Wordtune writes only in English. It can translate text from other languages into English, which helps for messages but not for drafting a German novel.
AIWriteBook: Write the whole book in German, with the outline, characters and editor all in German (37 languages are supported). When it is done, translate the whole book into English, including chapters, characters, cover and metadata.
AIWriteBook. Writing and translating at book length is outside what Wordtune does.
Price per job, not per rewrite
Wordtune meters rewrites per day. AIWriteBook meters what the AI writes, and the planning stage costs nothing.
Wordtune
- Basic$010 rewrites and suggestions a day, 3 summaries a month
- Advanced$6.99/mo$4.89/mo billed yearly, 30 rewrites a day
- Unlimited$9.99/mo$6.99/mo billed yearly, unlimited rewrites and summaries
AIWriteBook
- Free$0Outline, characters and chapter one
- Plansfrom $12/moBilled yearly
- Credit packsfrom $20250 credits for $20, no subscription
Many authors keep both: Wordtune for email and social posts, AIWriteBook for the manuscript. If you used Wordtune to make AI drafts sound more natural, our free AI text humanizer does that for a passage too, and the AI writing assistant guide compares the other options.
Wordtune alternative FAQ
Can Wordtune write a book?
Wordtune rewrites, expands and continues text you give it, a sentence or paragraph at a time. It has no outline, characters or chapter structure, so a book would be assembled by hand. AIWriteBook is built around the book: outline, chapters, editing and publishing files.
Is AIWriteBook a good Wordtune alternative?
For books, yes. For quick rewrites of emails and posts, Wordtune is faster because it sits in your browser. Many writers use Wordtune for everyday writing and AIWriteBook for the manuscript.
How do the prices compare?
Wordtune has a free Basic plan with 10 rewrites a day, Advanced at $6.99 a month and Unlimited at $9.99 a month, both cheaper billed yearly. AIWriteBook is free for your outline and first chapter, with plans from $12/mo billed yearly and one-time packs from $20.
Can I edit my own writing in AIWriteBook the way I do in Wordtune?
Yes. Ask the chapter chat to make a passage tighter, warmer or more formal. The change appears as a diff, and you accept or reject each part of it.
Does AIWriteBook write in languages other than English?
Yes. You can write a book in any of 37 languages and translate a finished book into another one.
Where to go next
- AI writing assistants for authorsHow sentence tools, chat tools and book tools differ.
- First draft writing tipsGet to the end of the draft before you polish a single sentence.
- AIWriteBook vs JasperThe marketing-copy AI that authors also try for books.
- AIWriteBook vs ChatGPTWhat changes when the chat window has to hold a whole novel.
Stop polishing sentences. Start the book
Your outline, characters and first chapter are free.
- 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