GPTZero vs Undetectable.ai
GPTZero scores higher overall, 3.5 against 2.7 of 5.0, and leads in 5 of the six categories to 1. Which matters depends on the categories you weigh most.
Independently evaluated by huby · 2026-10-22 · scores free to read and cite
Overall scores
Category by category
A category is won on the higher score. Equal scores are counted for neither.
What the evaluation found
GPTZero
Strongest category: Use Cases & Pricing
GPTZero's strategy targets a wide audience with a flexible model, offering a free version for basic use, fixed-price plans for professionals, and usage-based API access for developers and large organizations. The service integrates directly into common workflows through add-ins for Microsoft Word and Google Docs, as well as major Learning Management Systems like Canvas. For enterprise clients, a central dashboard allows for bulk user management and cost monitoring, while the API enables deep, custom integration into existing software.
GPTZero Research Brief, $35 →Undetectable.ai
Strongest category: Quality
Undetectable.ai demonstrates highly inconsistent performance, excelling at identifying simple, unedited AI or human writing but struggling significantly with more complex material. In controlled huby testing, the tool correctly identified all purely human-written documents but failed to flag two-thirds of AI-generated text that was edited or designed to be evasive. This performance gap extends to its rewriting feature, where the paid version can bypass some detectors while the free version is completely ineffective.
Undetectable.ai Research Brief, $35 →Go deeper on either one
The scores above are free. A Research Brief adds every subcategory scored, the assessment behind each one, and who should consider it - six pages, in the shape a buying decision actually needs.
Common questions
Is GPTZero or Undetectable.ai better?
On huby's independent evaluation, GPTZero scores 3.5 against 2.7 for Undetectable.ai, and leads in 5 of the six categories. Neither is better at everything - the category table above shows where each one leads.
How are GPTZero and Undetectable.ai scored?
Both are evaluated against the same framework, on the same 1.0-5.0 scale, from evidence tiered by source. The scores were published 2026-10-22. huby takes no payment to change a score or a rank.
How many AI detectors has huby evaluated?
9 text detectors, all against the same framework, which is what makes these two comparable at all.
What do I get that is not on this page?
This page is free and always will be: both overall scores, all six category scores and a verdict. A Research Brief adds the subcategory scores, the written assessment behind each one, and who should consider the product.