Prices in GBP. Verified monthly. Always check the provider's site for the latest.
Pros & cons
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
Kling AI
Pros
+Wide creative tooling: text-to-video, image-to-video, AI avatars, lip-sync, and motion control
+Developer API available with per-second pricing for video generation (klingai.com/dev)
+Kling 3.0 supports up to 4K resolution and native audio generation
+International-facing platform with English-language interface
Cons
−Consumer subscription pricing not verifiable from official English-language pages
−GDPR, SOC2, and ISO 27001 compliance not confirmed from official sources
−Data residency and training practices not publicly documented in accessible pages
Our take— QuillBot wins
Based on our comparison of published pricing, features, and compliance data, QuillBot pulls ahead with a free tier. Kling AI counters with API access. QuillBot scores 7.3/10 to Kling AI's 7.0/10. Pick QuillBot if you need a free tier; pick Kling AI if you need API access.