Proofreading Software for Authors: Which Prices Could Be Read and Which Could Not

ProWritingAid is the only proofreading tool here whose pricing page gave a full, readable price list on 2026-11-08, so it is the easiest to cost out; for Grammarly, LanguageTool, Hemingway and AutoCrit, the pages read were partial or conflicting. These notes rest on published pages. We have not run our own error-seeded chapter, so we make no claim about which catches more mistakes.

The criteria

Without an accuracy test, the picks here rest on what a vendor's page lets you verify: whether a full price list is shown, how long a text the tool will check, what the page says about storing your text, what refund terms apply, and whether the tool offers rewriting features that bear on KDP's AI rule. Where a page was silent, the table says so.

What each price page showed

Only the first row is a complete read. The rest tell you what was missing.

Because the ProWritingAid and Grammarly pages show monthly figures that depend on billing period, compare annual cost, not the headline number.

Limits and rules the pages state

Price is only one part of fit for a 90,000-word manuscript, so here is what each page said about length, privacy and refunds.

• ProWritingAid: Free checks 500 words at a time, while Premium and Premium Pro are listed for any length. Daily limits apply to some AI-style features: Chapter Critiques are 1 a day on Premium and 30 a day on Premium Pro, and Rephrases are 10 a day on Free and unlimited on paid plans. The page says it supports English only. Yearly and lifetime plans have a 3-day money-back window, monthly plans are not refundable, and paid plans auto-renew. It says "We never keep your work or any text entered into our editor", and it makes no statement about AI training.
• Grammarly: the page read shows Free with 100 AI prompts a month and Pro with 2,000. Pro lists full-sentence rewrites, AI-generated text detection and plagiarism detection. The page does not give a document length limit or a full refund policy.
• LanguageTool: Free is 2,000 characters per text field and Premium is 150,000 characters per field. The page says texts written with the browser add-on are usually not saved, while texts written in its editor are saved and available across your devices. It lists apps for Windows, macOS and iOS and plugins for Google Docs, Word, Apple Pages and LibreOffice.
• Hemingway: the page makes no data or privacy statement and lists no prices.
• AutoCrit: the page makes no privacy or training statement and no trial is mentioned.

The 150,000-character figure converts to about 25,000 words if you assume six characters per word including spaces, our rough conversion and an estimate. A full novel is longer, so a book-length edit would run in sections.

What it costs over time (our arithmetic, an estimate)

ProWritingAid is the only tool where all the needed figures were readable, so here is its cost over time, assuming the listed prices hold. Premium costs $360 over twelve months if paid monthly ($30 x 12), against $120 billed yearly, a gap of $240. The $399 lifetime price equals about 3.3 years of the $120 yearly plan. Premium Pro at $144 a year reaches $720 over five years, against the $699 lifetime price, which is roughly the break-even at about 4.9 years. Those sums assume you keep using it that long. The page's refund window for yearly and lifetime plans is only three days, so use the free plan first.

For Grammarly, two extractions of the page differed on the billing period for Pro at $12, so we compute no annual figure; confirm the period at checkout.

What the paid plans add

The tiers differ in what they unlock, not only in price, so it helps to know what you would be paying for.

• ProWritingAid: the free plan lists grammar, spelling and punctuation checks, a thesaurus and document type selection. Premium adds unlimited line editing, a custom style guide, more than 25 analysis reports, a custom dictionary, commenting and sharing, and Outline Crafter. Premium Pro adds higher daily limits for Chapter Critiques and other idea tools, plus workshops, critique sessions and networking events. Whether you want a community tier is a separate question from whether you want a proofreader. The page lists Google Docs, Microsoft Office, a desktop editor and a web editor, and does not mention Scrivener or name manuscript formats.
• Grammarly: Free adds tone visibility and Pro adds full-sentence rewrites, tone adjustment, inclusive-language checks, citation consistency and plagiarism detection. Several of those are aimed at business and academic writing, and the page does not say which suit fiction.
• LanguageTool: Premium adds a Style Guide, unlimited AI sentence paraphrasing and extra checks for English, German, French, Spanish, Dutch, Polish and Portuguese. The page does not say how many languages the free tier covers.
• Hemingway: the page highlights fixing flagged issues, grammar and tone, and links to an AI proofreader, without describing how either works.

None of the pages read says how the tools treat dialogue, dialect or deliberate fragments, which are the places fiction trips a grammar checker. That is a question for your own chapter and the free plan, not for a vendor page.

Choosing without an accuracy comparison

Without our own trial, choose on what the pages document.

• Want a clearly priced option, including lifetime: ProWritingAid.
• Need long documents checked in a browser: LanguageTool's page states a 150,000-character limit per field on Premium versus 2,000 free, so check where your chapter size falls once you can see its price.
• Want the strongest privacy wording on the page: ProWritingAid's statement that it does not keep your text is the most specific of the pages read; LanguageTool distinguishes its add-on from its editor; the others made no statement.
• Want to try before paying: Hemingway lists a two-week trial, ProWritingAid and Grammarly list free plans, and LanguageTool lists a 14-day money-back period.
• Want a story-focused tool: AutoCrit lists genre comparison and automated reader features, but its prices contradict each other, so confirm with the vendor first.

Proofreading and KDP's AI rule

KDP's AI-assisted definition includes using AI to "edit, refine, error-check"; the page does not name grammar checkers or set a threshold, so a tool that rewrites whole passages is a different case: text "created by an AI-based tool" is AI-generated, even after substantial edits. Several of these tools list rewriting features, namely Grammarly's full-sentence rewrites, ProWritingAid's Rephrases and LanguageTool's AI sentence paraphrasing. Keep the tool to suggestions and make the changes yourself. See our KDP disclosure guide and using AI without losing your voice.

What to confirm before paying

1. Billing period and total at checkout, since two extractions of Grammarly's page differed on the period and LanguageTool's prices did not load.
2. Maximum text length per check against your chapter size.
3. What the privacy policy says about storing and training on your text, because several pages say nothing.
4. Refund terms, noting ProWritingAid's three-day window on yearly and lifetime plans.
5. Whether the rewriting features are on and whether you intend to use them.

Downsides and who should skip

These tools suggest; they do not replace a human proofreader for a book going to readers. Skip a paid plan if the free tier covers your chapters. Skip lifetime pricing until you have used the free plan for a full chapter, given the short refund window. Skip any tool whose price you cannot see until the vendor shows it. For drafting tools, see best AI for fiction writers.

More tools and guides are in the AI drafting tools hub.

Last verified 2026-11-08. Rules and prices change: check the linked primary page before you rely on this.