Prices in GBP. Verified monthly. Always check the provider's site for the latest.
Pros & cons
AutoGPT
Pros
+Fully open source — self-host for free with Docker
+Pioneer of the autonomous agent paradigm
+Maximum flexibility for technical users
+No vendor lock-in on the self-hosted path
Cons
−No free hosted tier — cloud plans billed annually only
−GDPR and SOC2 not confirmed from official sources
−Team plan listed as 'coming soon' — no multi-user cloud option yet
−Steeper learning curve than no-code alternatives
QuillBot
Pros
+Free tier paraphrases up to 125 words with no time limit
+9 paraphrase modes including Formal, Simple, Creative, and Expand
+Premium at £4/mo (annual) is the lowest price in the writing category
+Plagiarism checker and AI Detector bundled with Premium
Cons
−GDPR and SOC2 not confirmed from official sources
−Free tier capped at 125 words per paraphrase — limiting for longer content
−Focused on paraphrasing — not a full-document AI writing assistant
Our take— QuillBot wins
Based on our comparison of published pricing, features, and compliance data, QuillBot pulls ahead with a free tier. AutoGPT counters with API access. QuillBot scores 7.3/10 to AutoGPT's 7.1/10. Pick QuillBot if you need a free tier; pick AutoGPT if you need API access.