Grammarly
Catching typos and clarity issues everywhere you write, including the Substack editor
Directory / Editing & Proofreading / QuillBot
QuillBot
Our verdict: Useful for tightening a stubborn paragraph. Don't lean on it for whole posts, because readers subscribe for your voice.
Best for
Paraphrasing, summarizing and quick rewrites
Pricing
Free; Premium $19.95/mo or $99.95/yr.
Source: QuillBot help center
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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