The Best Open Source Grammarly AlternativesTop Grammar Checkers & AI Writing Tools like Grammarly

The best open source alternative to Grammarly is LanguageTool. If that doesn't suit you, our users have ranked more than 100 alternatives to Grammarly and many of them is open source so hopefully you can find a suitable replacement. Other interesting open source alternatives to Grammarly are Harper, Onit AI, Grammalecte and Eloquent Proofreading Assistant.

filter to find the best alternatives

Grammarly alternatives are mainly Grammar Checkers, but if you're looking for AI Writing Tools or Text to Speech Services you can filter on that. Other popular filters include Open Source, Windows, iPhone, Linux, iPad, Apache OpenOffice and Android. You can also filter by region, for example EU-based alternatives if you prefer software developed in the European Union. These are just examples - use the filter bar below to find more specific alternatives to Grammarly.

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Grammarly alternatives page was last updated Jan 14, 2026

LanguageTool
187 likes
Proofreading software compatible with LibreOffice, Word, Firefox, and Chrome. Supports 20+ languages, offering two tiers: free and premium, with features like customizable checks, Microsoft add-on, and error detection in gender, ISBN, and IBAN. Offers open-source web and desktop versions.
104 LanguageTool alternatives
Cost / License
Freemium
Open Source (LGPL-2.1)
Application types
Grammar Checker
AI Writing
Origin
Germany
EU
Platforms
Mac
Windows
Linux
Online
iPhone
iPad
Microsoft Edge
ONLYOFFICE
Google Chrome
Microsoft Outlook
Safari
Visual Studio Code
Microsoft Word
Eclipse
TinyMCE
Google Docs
Thunderbird
Vim
Cloudron
Sublime Text
GNU Emacs
Opera
Gmail
LibreOffice
Apache OpenOffice
Mozilla Firefox
LibreOffice - Writer
+2
Is LanguageTool a good alternative to Grammarly?

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11comments
LanguageTool vs Grammarly Comments

Top Positive Comment
RemovedUser
May 24, 2020
6
Open source, cheaper, works in more languages.
Review by a new / low-activity user.
Top Negative Comment
Guest
Apr 21, 2020
14
It doesn't work very well. For example, it shows all is good if I type in the following: "Can you do plan by yourself? Yoda I speak like and check grammar I do. "
Review by a new / low-activity user.
Jan Klass
CommentApr 20, 2025
1
Note: Despite being listed here as "Country of Origin: DE, EU", while the website imprint does list a GmbH (German business), the privacy policy does not mention it; it mentions only the parent org Learneo and it includes data transfer to outside the EEA and into the US.
3 of 11 comments
LanguageTool is Freemium and Open SourceGrammarly is Freemium and Proprietary
LanguageTool is Privacy focusedGrammarly is not according to our users
Harper
13 likes
Harper is an English grammar checker designed to be just right. I created it after years of dealing with the shortcomings of the competition.
Cost / License
Free
Open Source (Apache-2.0)
Application type
Grammar Checker
Origin
United States
Platforms
Self-Hosted
WebAssembly
Visual Studio Code
Mac
Linux
Windows
Homebrew
Neovim
Is Harper a good alternative to Grammarly?
Onit AI
10 likes
Onit AI Copilot offers a comprehensive desktop AI chat assistant with local processing and multi-provider support. It prioritizes customization, extensibility, and user privacy by operating entirely on-device without needing an internet connection, ensuring data security.
Cost / License
Free
Open Source
Origin
United States
Platforms
Mac
+2
Is Onit AI a good alternative to Grammarly?
Ad
LanguageTool
Proofreading software compatible with LibreOffice, Word, Firefox, and Chrome. Supports 20+ languages, offering two tiers: free and premium, with features like customizable checks, Microsoft add-on, and error detection in gender, ...

https://languagetool.org
Learn More
Grammalecte
33 likes
Grammalecte is a French grammar checker.
40 Grammalecte alternatives
Cost / License
Free
Open Source
Application type
Grammar Checker
Origin
France
EU
Platforms
Mac
Windows
Linux
Chrome OS
Google Chrome
Python
Thunderbird
Vim
Sublime Text
GNU Emacs
Pluma
LibreOffice
Mozilla Firefox
LibreOffice - Writer
ONLYOFFICE
+2
Is Grammalecte a good alternative to Grammarly?
Eloquent Proofreading Assistant
4 likes
Eloquent is a proofreading software for English, Spanish, French, German, Portuguese, Polish, Dutch, and more than 20 other languages. It finds many errors that a simple spell checker cannot detect.
Cost / License
Free
Open Source (GPL-3.0)
Application type
Grammar Checker
Origin
United States
Platforms
Linux
Flathub
Flatpak
Is this a good alternative to Grammarly?
Vale
2 likes
Vale is an open-source, command-line tool that brings your editorial style guide to life.
Cost / License
Free
Open Source (MIT)
Origin
United States
Platforms
Windows
Mac
Linux
Is Vale a good alternative to Grammarly?
Typopo
2 likes
Typopo fixes microtypography errors that often require attentive eye and knowledge of local typography rules. It works for English, German, Slovak, Czech and Rusyn texts.
Cost / License
Free
Open Source (MIT)
Platforms
Online
Software as a Service (SaaS)
Is Typopo a good alternative to Grammarly?
RewritePal
6 likes
RewritePal is a free, AI-powered tool designed to make your writing clear, compelling, and tailored to any audience. Whether you're a student, professional, or content creator, RewritePal helps you transform paragraphs into polished, reader-friendly text in seconds.
17 RewritePal alternatives
Cost / License
Free
Open Source (MIT)
Application types
AI Writing
Grammar Checker
Platforms
Online
Is RewritePal a good alternative to Grammarly?
Editsaurus
14 likes
Highlights potential pitfalls in your writing to encourage good habits.
Cost / License
Free
Open Source (MIT)
Application type
Grammar Checker
Origin
United States
Alerts
Discontinued
Platforms
Online
Self-Hosted
Is Editsaurus a good alternative to Grammarly?
proselint
2 likes
Writing is notoriously hard, even for the best writers, and it's not for lack of good advice — a tremendous amount of knowledge about the craft is strewn across usage guides, dictionaries, technical manuals, essays, pamphlets, websites, and the hearts and minds of great...
Cost / License
Free
Open Source (BSD-3-Clause)
Platforms
Linux
Python
Is proselint a good alternative to Grammarly?
Grammark
2 likes
Grammark helps improve writing style & grammar and teaches students to self-edit. Basically, it finds things that grammarians consider bad, highlights them, and suggests improvements.
Cost / License
Free
Open Source (GPL-3.0)
Application type
Grammar Checker
Platforms
Online
Self-Hosted
Is Grammark a good alternative to Grammarly?

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2comments
Grammark vs Grammarly Comments

pmilsom
Positive commentOct 31, 2019
0
Grammark is very proficient Authors protector. It has to be used as a service and can't be downloaded into Libre Office. But it does a wonderful job in the smaller offerings that can be managed through a service.
Review by a new / low-activity user.
Guest
Positive commentDec 8, 2019
0
Grammark has a "lean in" style with active voice that I like. It's a nuance but important.
Review by a new / low-activity user.
Grammark is Free and Open SourceGrammarly is Freemium and Proprietary
Scramble
Like
Scramble is an open-source Chrome extension that leverages AI to enhance your writing directly in your browser. It's designed to be a more customizable and privacy-respecting alternative to Grammarly.
Cost / License
Free
Open Source (MIT)
Application type
Grammar Checker
Platforms
Google Chrome
Is Scramble a good alternative to Grammarly?

12 of 20 Grammarly alternatives

The Best Open Source Grammarly AlternativesTop Grammar Checkers & AI Writing Tools like Grammarly

Alternatives list

LanguageTool

Cost / License

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LanguageTool vs Grammarly Comments

Harper

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Onit AI

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Grammalecte

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Eloquent Proofreading Assistant

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Vale

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Typopo

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RewritePal

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Editsaurus

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Alerts

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proselint

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Grammark

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Grammark vs Grammarly Comments

Scramble

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