Lexicon review
A free, open-source editor for local proofreading, rewriting, and document workflows.
Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
Lexicon is a free, open-source desktop writing application for drafting, proofreading, rewriting, tone adjustments, and document export. It is designed for writers who want offline-capable editing without an account or subscription. The application runs on Windows, macOS, and Linux, and combines local grammar, spelling, and style proofreading with rich-text editing. Its editor supports headings, lists, tasks, tables, images, and code blocks, making it suitable for both standard writing and structured documents.
Its strongest distinction is the breadth of local writing assistance. Inline suggestions can be applied or dismissed, while tone detection, clarity checks, and readability scoring add review beyond basic spelling correction. Lexicon also includes local AI rewriting, summarization, and tone transformations. For users with custom terminology, the personal dictionary provides a way to preserve preferred vocabulary. Document workflows extend to import and export for common formats, including PDF and Markdown. Optional local AI connectivity through Ollama and LM Studio gives technically oriented users additional model options.
Lexicon is a good fit for privacy-focused writers who want an open-source desktop workflow with proofreading, rewriting, and document handling in one application. Its browser extension broadens proofreading to supported web fields, but the extension is beta and requires the desktop app to be running. That makes it less suitable for users seeking a mature, browser-first checker that works independently of a desktop application. Writers who prioritize local processing, offline-capable editing, and control over AI connections should consider Lexicon; those who need a standalone web workflow should look elsewhere.
Lexicon pros and cons
- Where it wins
- Local grammar, spelling, style, tone, and readability tools
- Rich editing plus PDF and Markdown import/export
- Open-source desktop apps with Ollama and LM Studio support
- Where it doesn't
- Browser extension is beta
- The extension requires the desktop app to be running
- Local AI features require bundled models or configured local servers
Lexicon fact sheet, pricing and score →
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