LanguageTool vs QuillBot

LanguageTool

• People who write in several languages, not only English
• LibreOffice, Thunderbird and Apple Pages users who want a checker add-on
• Developers who need a proofreading API or a checker they can host themselves

QuillBot

• Students and writers who need to reword or shorten existing text
• People who want paraphrasing, grammar and citation tools in one account
• Teams of 2 or more that want centralized billing

LanguageTool

• The free Basic plan checks 2,000 characters per text field and allows 3 AI rephrasings a day.
• There is no free trial of Premium; LanguageTool offers a 14-day money-back guarantee instead.
• Monthly billing is $24.90, more than four times the per-month cost of the annual plan.
• Apps are listed for Windows, macOS and iOS; no Android app appears on the site.

QuillBot

• The free plan paraphrases at most 125 words at a time and offers only the Standard and Fluency modes.
• Free summaries are capped at 1,200 words; Premium raises the cap to 6,000.
• Plagiarism checking is a Premium feature and is limited to 25,000 words a month.
• The pricing page leads with annual billing at $8.33 a month; the iOS app lists monthly billing at $19.99.

LanguageTool

Grammar, spelling and style checks

Checks grammar, punctuation, spelling, casing and style. Premium adds more than 20,000 extra checks for English, German, French, Spanish, Dutch, Polish and Portuguese.

AI paraphrasing

Rephrases a sentence to be more formal, more fluid or shorter. Basic accounts get 3 rephrasings a day and Premium removes the limit.

Long-text checking

Premium checks up to 150,000 characters per text field, against 2,000 on the Basic plan.

Style guide and dictionaries

Custom rules enforce consistent wording. Teams share a style guide and a dictionary of approved terms, with admins deciding who can add to them.

Add-ons and apps

Browser add-ons for Chrome, Edge, Firefox, Safari and Opera, plugins for Google Docs, Word, Apple Pages and LibreOffice, email add-ons, and apps for Windows, macOS and iOS.

Open-source core and API

The core checker is open source, with code on GitHub, and users can set up their own LanguageTool server. A hosted Proofreading API accepts up to 60,000 characters per request.

QuillBot

Paraphraser

Rewords text in built-in modes: Standard and Fluency on the free plan, 9 modes plus unlimited custom modes on Premium. It paraphrases in 23 languages.

Grammar Checker

Fixes basic grammar errors on the free plan and adds advanced writing suggestions and tone insights on Premium. Grammar correction covers 6 languages.

AI Detector and Humanizer

The AI Detector flags AI-generated content, and the Humanizer rewrites text so it reads more naturally. Free use of both is limited; Premium gives full access.

Summarizer and Translator

Summarizes up to 1,200 words on the free plan and 6,000 on Premium, which adds custom summaries. The Translator covers more than 40 languages.

Plagiarism and citation tools

Premium scans up to 25,000 words a month for accidental plagiarism, and the Citation Generator formats references in APA, MLA and Chicago styles.

Extensions and apps

Chrome, Edge and Safari extensions, a Word add-in, macOS and Windows apps, and iOS and Android keyboards and apps. Premium runs on up to 10 devices at a time.

LanguageTool

• Basic$0

  Grammar, punctuation and spelling checks on up to 2,000 characters per text field, with 3 AI sentence rephrasings a day.

• Premium$5.83

  per month, billed annually ($69.90); $24.90 billed monthly

  Up to 150,000 characters per text field, 20,000+ extra checks, unlimited AI paraphrasing and a personal style guide. Also $49.90 a quarter or $119.80 for 2 years.

• Teams$66.40

  per user / year, for a team of 2 users

  Every Premium feature plus user management, a team style guide and a team dictionary. Sold from 2 users, with a lower per-user price for larger teams.

QuillBot

• Free$0

  Paraphrase up to 125 words in 2 modes, fix basic grammar errors, summarize up to 1,200 words, and use the Humanizer and AI Detector with limits.

• Premium$8.33

  per month, billed annually

  Full paraphrasing in 9 modes plus custom modes, advanced grammar suggestions, 6,000-word summaries, the full AI Detector and plagiarism checks on 25,000 words a month.

• Team Plan$7.50

  per seat / month, billed every 12 months ($89.95), for 2-10 seats

  All Premium features plus writer-management dashboards and centralized billing. $6.66 a seat for 11-50 seats and $5.83 for 51 or more.

LanguageTool

• Annual discount

  Longer billing terms cost less per month

  Premium is $24.90 billed monthly, $49.90 a quarter, $69.90 a year or $119.80 for two years, which works out to about $5.83 and $4.99 a month on the two longest terms.

• Education

  Up to 20% off for students and educators

  Students, teachers and professors can claim an educational discount of up to 20% off a Premium subscription.

• Other savings

  Team seats priced below individual plans

  On Teams, each seat costs less than the $69.90 individual annual price: $66.40 per user for 2 users and $62.91 per user from 10 users.

• Other savings

  Limited-time 20% discount on Premium

  The pricing page was advertising a limited-time 20% discount on Premium, with a countdown, when it was checked on 2026-10-05.

QuillBot

• Annual discount

  Annual billing marked as 58% off

  The pricing page labels annual billing 58% off the monthly rate, which brings Premium to $8.33 a month. In the iOS app the plans are $99.99 a year or $19.99 a month.

• Other savings

  Team seats cost 10% to 30% less

  Team plans are $7.50 a seat per month for 2-10 seats, $6.66 for 11-50 and $5.83 for 51 or more, billed every 12 months and labeled as 10%, 20% and 30% savings.