Make AI text
sound like you.

Yes — at making AI drafts read naturally. Refrazr changes sentence architecture and the statistical rhythm of word choices instead of swapping synonyms. Those are the patterns that make text feel machine-written: sentences that march in lockstep, transitions that land on schedule, vocabulary that never wanders. Simple paraphrasers reword the surface and leave that structure in place.

Yes. Turnitin's AI indicator runs on every academic submission and flags text with low per-token perplexity — the statistical fingerprint LLMs leave behind when each word choice is too predictable. Structural rewriting shifts that fingerprint in a way synonym swapping can't, because it changes the probability of every next word rather than individual tokens. Full per-detector breakdown at /methodology.

Turnitin does not look for vocabulary or plagiarism — it measures per-token probability. ChatGPT and other LLMs choose statistically-likely tokens at every position, so the cumulative perplexity stays low. Turnitin computes that perplexity and flags it. Refrazr breaks the chain by restructuring sentences, which forces the conditional probability of each next word to shift, raising entropy across the whole passage.

Main differences: Refrazr Pro $6.99/mo vs Undetectable.ai $19/mo — roughly 3× cheaper. Refrazr publishes the full methodology at /methodology; Undetectable.ai keeps it closed. Refrazr exposes an API + MCP server for Cursor/Claude; Undetectable.ai does not. Refrazr offers a 7-day no-questions refund. Questions? hello@refrazr.com

It depends on context, not on the tool. Submitting AI-generated work as your own original thinking in an academic class that prohibits it is dishonest. Using AI to draft, then rewriting in your own voice, then running the result through a humanizer to clear false-positive flags — that is what most professional writers and second-language students actually do. The tool itself is neutral; the policy that applies to your situation is the relevant question.

Refrazr runs your text through a three-step pipeline. First a fast heuristic pass classifies how hard the draft is to rewrite — no LLM call yet. Then the whole draft goes to the model in one pass, under a compact instruction to write it the way a sharp person actually would, with a hard rule that no name, number, or claim gets changed or invented. A light cleanup pass catches whatever the model leaves behind. Full pipeline and benchmark at /methodology.

Yes. Refrazr does not store your text. The process is: receive text, rewrite, return result, discard. Nothing is logged, shared with third parties, or used for training. The API runs over HTTPS with end-to-end encryption.

Output from simple synonym-swap tools — often, yes. Turnitin's AI detection reads per-token probability patterns, not word choice, and a reworded sentence keeps the original probability skeleton. Refrazr rewrites whole sentence structures instead, which changes the statistical profile a detector reads. No tool can promise a specific result on someone else's detector — that's why the editor shows you the pattern analysis before you copy.

Pick a tool that rewrites structure, not just words. Refrazr works at the structural level — it changes how sentence lengths vary, where transitions fall, and how vocabulary spreads across a passage. Those are the qualities that decide whether writing reads naturally. QuillBot-style paraphrasers swap words and keep the original skeleton. Full technical breakdown at /methodology.

Yes, there is a free tier. Free users can humanize up to 500 words per day with no credit card required. Word packs start at $1.99 (one-time, no subscription), and Pro at $6.99/month gives unlimited words.

Different tools for different jobs. QuillBot is a paraphraser — it rewords, but the underlying sentence rhythm and AI vocabulary survive, which is exactly what detectors flag. Refrazr targets the statistical fingerprint detectors actually look at: sentence-length variance, transition density, vocabulary distribution. QuillBot changes what the text says; Refrazr changes how it was written.

A paraphraser rewrites text to express the same idea differently. An AI humanizer goes deeper — it rebuilds the statistical patterns of the writing itself: the rhythm of sentence lengths, where transitions land, how vocabulary distributes. A paraphraser changes what the text says. A humanizer changes the shape it was written in.

No. Preserving meaning is the primary constraint. The prompt instructs the model to maintain all factual claims, arguments, and conclusions while only changing structural and stylistic patterns. If a rewrite drifts, use Re-humanize — each pass varies slightly.

We process the full text up to your remaining quota and return that humanized chunk plus a note showing where it stopped. The original text isn't truncated — you keep your draft. Upgrade to Pro for unlimited words, or buy a one-time pack starting at $1.99 (3,000 words) and finish the rest.

Word-pack credits never expire. Buy 30,000 words today, use them three years from now — they'll still be there. Subscriptions reset monthly: Pro and Business include unlimited usage so the question is moot. Free-tier daily allowance resets at midnight UTC.

Yes — 7 days, no questions asked. Email hello@refrazr.com from the address you used to buy and we issue a refund within 24 hours. We don't ask why, we don't try to retain you. If Refrazr didn't work for your text, we shouldn't have your money.