Grammarly
Catching typos and clarity issues everywhere you write, including the Substack editor
Directory / Editing & Proofreading / LanguageTool
LanguageTool
Our verdict: Strong grammar checking across many languages, and much cheaper per year than monthly billing.
Best for
Multilingual writers and anyone who wants a Grammarly alternative
Pricing
Free; Premium $24.90/mo monthly or $69.90/yr.
Source: LanguageTool help center + third-party price tracker
Website
Last checked
2026-10-18
Disclosure: We have no affiliate relationship with this vendor. StackKit is independent and not affiliated with Substack Inc. Spot an error? Email hello@stackkit.ink.
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