LanguageTool

LanguageTool is an AI-powered writing assistant and proofreading tool designed to check grammar, spelling, and style across more than 30 languages. Beyond basic spell-checking, it detects complex grammatical errors, punctuation mistakes, and stylistic shortcomings. It can be used directly in web browsers, as an extension for office suites like Microsoft Word and Google Docs, or via standalone desktop applications.

In addition to standard error detection, LanguageTool features an intelligent rephrasing tool that allows users to adjust sentences into various tones, such as formal, fluent, concise, or simple. The software respects language variations, such as distinguishing between American and British English or German and Swiss German. Users can also maintain personal dictionaries to exclude specialized terminology or brand names from error flagging.

LanguageTool is widely adopted by individual writers, educational institutions, content creators, and corporate teams seeking to ensure text quality in daily communication. Beside its cloud-based infrastructure, the underlying core is available as open-source software, enabling self-hosted deployments for privacy-sensitive enterprise environments.

• AI-Driven Grammar and Style Checking — LanguageTool analyzes text for spelling mistakes, grammatical flaws, and punctuation issues across over 30 languages. It offers instant correction suggestions alongside concise rule explanations.
• Sentence Rephrasing Tool — The rephrasing feature enables users to rewrite sentences in different tones with a single click. Options include adjusting text to be more formal, fluent, concise, or simplified.
• Multi-Platform Integrations — LanguageTool integrates smoothly as a browser extension, desktop app, and add-in for tools like Microsoft Word, Google Docs, and LibreOffice. This allows continuous proofreading within existing writing workflows.

LanguageTool is tailored for students, authors, translators, marketers, and business professionals who need error-free written communication. It is particularly valuable for individuals working in multilingual environments or writing in non-native languages.

A marketing manager prepares a bilingual press release in English and German. While drafting inside Google Docs, LanguageTool continuously checks grammar and punctuation in real time. For overly complex or wordy sentences, the manager relies on the rephrasing feature to generate alternative drafts. They select a formal and concise style option to improve overall clarity and tone. This enables the team to publish error-free content quickly without waiting for external proofreaders.

• LanguageTool is tailored for students, authors, translators, marketers, and business professionals who need error-free written communication. It is particularly valuable for individuals working in multilingual environments or writing in non-native languages.
• A marketing manager prepares a bilingual press release in English and German.
• AI-Driven Grammar and Style Checking: LanguageTool analyzes text for spelling mistakes, grammatical flaws, and punctuation issues across over 30 languages. It offers instant correction suggestions alongside concise rule explanations.
• Sentence Rephrasing Tool: The rephrasing feature enables users to rewrite sentences in different tones with a single click. Options include adjusting text to be more formal, fluent, concise, or simplified.
• Multi-Platform Integrations: LanguageTool integrates smoothly as a browser extension, desktop app, and add-in for tools like Microsoft Word, Google Docs, and LibreOffice. This allows continuous proofreading within existing writing workflows.

LanguageTool is not designed as a standalone machine translation engine like DeepL, nor as a generative text generator to write full articles from scratch. Users seeking automated content creation from prompts should use dedicated generative AI writing tools instead.

• DeepL — Freemium · HQ: Köln, Germany · GDPR / EU
• Grammarly — Freemium · HQ: San Francisco, United States · Unclear