Thinking of switching?
Here is the honest version.
Every comparison below says where the other tool is still the better choice, because a page that never concedes anything is an advert rather than a comparison. All of our own performance numbers are measured and published, failures included.
Undetectable AI
Undetectable AI is a competent tool and one of the first in this category. Most people who go looking for an alternative are not leaving because it does not work. They are leaving because of the subscription, the account wall on the free demo, or because they want to know what the tool actually scores before they trust it with something that matters.
Read the comparison →QuillBot
QuillBot is genuinely good at what it was designed for, which is rewording text. The trouble is that people increasingly reach for it to solve a different problem, getting AI writing past a detector, and it was never built for that. Paraphrasing and evading a statistical classifier are different tasks, and a tool optimised for the first does not automatically do the second.
Read the comparison →StealthWriter
StealthWriter is an aggressive humanizer with a loyal following, and on the hardest text it can be effective. The two complaints that send people looking elsewhere are consistent: the price, particularly the lifetime tier, and output that sometimes reads awkwardly enough that a human reader notices even when a detector does not.
Read the comparison →Phrasly
Phrasly targets students, and for straightforward academic text it does a reasonable job. The reasons people search for an alternative are mostly practical: they want to try it without handing over an email first, they want to know what it really scores, and they do not want another monthly charge for a tool they need in bursts around deadlines.
Read the comparison →Read our own numbers first
Every tool in this category advertises a pass rate between 96 and 99.8 percent, and none of them publish a sample size, a date, a named detector or a failure rate. We measured 114 real production runs against hosted GPTZero and published everything, including the 16.7 percent that failed outright. Read that before you trust anyone on this subject, ourselves included.
Read the benchmark study