Comparison

Grammarly: Free AI Writing Assistance vs Quillbot

Grammarly: Free AI Writing Assistance and Quillbot both land on Worth it.

Grammarly: Free AI Writing Assistance

Worth it

Confidence: Medium

Buy the free tier for everyday writing . it is genuinely useful at $0.

Worth it

Confidence: Medium

Buy it if you're a student, non-native English writer, or blogger who wants cheap paraphrasing and grammar cleanup.

Grammarly: Free AI Writing Assistance versus Quillbot
Compare	Grammarly: Free AI Writing Assistance	Quillbot
Verdict	Worth it	Worth it
Best for	Students and academics	Students editing essays and theses
Who it's not for	Novelists fearing AI-detection flags	Anyone relying on its AI detector for high-stakes checks . accuracy is contested
Privacy	Third-party scan scores 89/100; official product security page published; no public CVEs found in reviewed sources.^³	No known public vulnerabilities found in the sources reviewed; GDPR/CCPA trust center is published, though it was named in a 2026 Chrome-extension privacy-risk report.
Support quality	No support evidence in sources	Only a BBB complaint found; little support data
Public sentiment	Casual users praise the free version, while some fiction writers report AI-detection accusations and fatigue with constant suggestions.^⁴	Reviews are broadly positive on value and paraphrasing quality, but users and independent testers distrust its AI detector.¹¹
Biggest gotcha	Advanced rewrites and tone tools sit behind Pro; the free tier nudges you to upgrade^¹	Don't trust its AI detector for high-stakes checks . testers and users report misses and false flags.

Anyone relying on its AI detector for high-stakes checks . accuracy is contested
Students trying to beat Turnitin . users report paraphrased text still gets flagged
Teams needing shared, collaborative writing workflows
Publishers wanting a human-editor replacement for serious manuscripts