NaturalWrite vs QuillBot: Different Tools, Same Problem
This is actually a more interesting comparison than it looks at first glance. NaturalWrite positions itself as an AI humanizer — a tool specifically designed to make AI-generated text undetectable. QuillBot is a general-purpose paraphraser that people happen to use for AI detection evasion. So you'd expect NaturalWrite to win this one easily. And it does win, but by less than you'd hope.
The core difference comes down to intent. QuillBot was built to help people reword text — for clarity, for variety, for avoiding self-plagiarism. It swaps synonyms, restructures sentences, and offers different “modes” for different styles. Using it to bypass AI detection is essentially a hack, and a poor one at that.
NaturalWrite was built to make AI text sound human. It includes a built-in AI detector so you can check your text before and after processing. The intention is right. The execution, unfortunately, leaves a lot to be desired.
Testing Both Against Real Detectors
We ran 150 AI-generated essays (mix of ChatGPT, Claude, and Gemini) through both tools and submitted the outputs to Turnitin, GPTZero, and Originality.ai. Here's what we found:
- NaturalWrite: ~65% bypass rate overall. It performed best against GPTZero (about 72% bypass) and worst against Originality.ai (about 55%). Turnitin was in the middle at 63%. Those numbers are decent on paper, but when one in three submissions still gets flagged, the tool isn't reliable enough for anything that matters.
- QuillBot: 42% bypass rate overall. No significant variation across detectors — it failed roughly equally against all of them. This makes sense because QuillBot doesn't target detection patterns at all. It just paraphrases, and sometimes that happens to be enough. Usually it isn't.
For comparison, SupWriter achieved 99%+ across every detector in the same test batch. The gap between dedicated humanization and paraphrasing-as-humanization is enormous.
NaturalWrite's Built-in Detector: Don't Trust It
One of NaturalWrite's selling points is its built-in AI detector. The idea is that you can check your text before submitting to make sure it passes. Sounds great in theory.
In practice, NaturalWrite's detector has a serious accuracy problem. In our testing, it reported text as “100% human” in many cases where Turnitin and GPTZero still flagged it as AI-generated. This creates a dangerous false sense of security. You process your text, NaturalWrite tells you it's clean, you submit it, and Turnitin flags it anyway.
We've written extensively about how AI detection tools vary wildly in accuracy. NaturalWrite's detector consistently rated its own output as more human than third-party detectors did. Whether that's intentional bias or just poor calibration, the result is the same: you can't rely on it.
QuillBot: Good Paraphraser, Bad Humanizer
We want to be fair to QuillBot here — it's not trying to be an AI humanizer. It's a paraphrasing tool, and at that job, it's pretty good. The seven modes offer genuine flexibility, and Standard and Fluency modes produce usable rewrites consistently. Our full QuillBot alternatives review covers this in depth.
But students and writers keep using it for detection bypass anyway, and the results are predictable. QuillBot changes surface-level features — vocabulary, sentence structure — while leaving the deeper statistical patterns untouched. Modern detectors like Turnitin look at things like token-level perplexity distributions, and no amount of synonym swapping changes those.
Why SupWriter Outperforms Both
The difference between SupWriter and tools like NaturalWrite or QuillBot is architectural. SupWriter doesn't just rewrite at the surface level — it rewrites at the pattern level. It adjusts the perplexity, burstiness, and sentence variation of text to match the statistical profile of genuine human writing.
That's why SupWriter achieves 99%+ bypass rates where NaturalWrite manages 65% and QuillBot struggles at 42%. It's not just a better paraphraser — it's a fundamentally different approach to the problem.
For $9.99/month with 300 free words to test, SupWriter offers the most reliable AI humanization available. If you're currently using NaturalWrite or QuillBot for detection bypass and getting inconsistent results, that's exactly the problem SupWriter was built to solve.
Related Resources
- Best QuillBot Alternative — Ranked by bypass rate
- NaturalWrite vs WriteHuman — Two humanizers compared
- NaturalWrite vs Undetectable AI — Which humanizer wins?
- Grammarly vs QuillBot — Grammar checker vs paraphraser
- Does Turnitin Detect AI? — Test results explained