quillbot has been around forever. it's the first thing most people try when they need to rewrite something. and for basic stuff — swapping a few words, cleaning up a sentence — it's fine.

but if you're trying to get past ai detectors, quillbot doesn't cut it anymore.

how quillbot works

quillbot is a synonym-level paraphraser. it takes your text, identifies words it can swap, and replaces them with alternatives. it has different modes — fluency, formal, creative — but they all work on the same principle. swap words, maybe rearrange a clause, output the result.

the sentence structure stays mostly the same. the rhythm stays the same. the overall pattern barely changes.

run quillbot output through gptzero and you'll see. the score drops a little but it still gets flagged. detectors learned to see through synonym swaps years ago.

how paraai works differently

paraai uses fine-tuned state-of-the-art models trained on actual human-text corpora. that's not marketing speak. it means our models learned how real people write — the messy parts, the inconsistencies, the weird rhythm that makes human writing human.

so when paraai rewrites a paragraph, it doesn't just swap words. it rebuilds the text from scratch. a three-sentence passage might come back as five shorter sentences. a formal tone might shift to conversational. the meaning stays but the surface form is completely different.

that's the difference between synonym replacement and actual rewriting.

the detector test

we've run this comparison a lot. take a chatgpt paragraph, run it through quillbot, then run it through paraai. put both through originality.ai.

quillbot usually brings the ai score down from ~95% to maybe 60-70%. still flagged.

paraai typically brings it under 15%. usually single digits. because the output doesn't just use different words — it has different structure, different rhythm, different patterns.

where quillbot still makes sense

quillbot is good for quick grammar fixes and basic rewording. if you're not worried about ai detection and just want to rephrase a sentence, it works. it's also cheaper.

but if you need untraceable ai writing — text that actually passes detectors and reads like a human wrote it — quillbot's approach doesn't go deep enough. paraai was built for that specific problem.

the bottom line

quillbot swaps words. paraai rewrites text. those sound similar but produce very different results when a detector is involved.