Grammarly vs QuillBot: which free AI agent wins?

Grammarly and QuillBot are two of the most compared tools in the writing category, and for good reason — both ship real free tiers and both are good enough that the winner depends on your specific workflow. This comparison breaks down where each one wins, where the other wins, and how to pick if you only have time to try one. Both tools ship durable free tiers and pricing pages without a "contact us" button. The differences show up once you push past casual use. Grammarly leans toward free tier catches the majority of real-world errors in emails and documents. QuillBot leans toward free tier is enough for students paraphrasing occasional paragraphs. Either is a valid default for most users in this category; the comparison table and winner-by-use-case below are for the cases where the difference actually matters. If you can only pilot one, pick the tool whose strength maps to the task you spend the most time on. Skim-comparing two tools wastes hours you could spend shipping. Use this page to form a shortlist, then open both tools and try the same real task on each — that's the only way to tell which one fits your workflow better. Full reviews for each are linked above, and both vendor sites let you sign up without a card.