GPTZero vs Undetectable AI (2026): Pricing, Features & Which to Choose

Who comes out ahead

Based only on the facts in our directory. The right pick still depends on the job you need done.

Lower starting price
Not comparable
Not comparable: Undetectable AI does not list a price
Free plan
Tie
Both have one
Higher rating
GPTZero
4.4 against 3.2
Same job?
Yes
Both are Writing tools

Side by side

Compared on	GPTZero	Undetectable AI
Our rating	4.4Better	3.2
Starts at	$15/mo	Free
Free plan	Yes	Yes
Category	Writing	Writing
Plans	From $15/mo	Free
Key features	AI-generated text detection across ChatGPT, Claude, Gemini, and other major LLMs Plagiarism detection bundled alongside AI detection in the same scan Hallucination detection that flags unsupported or fabricated claims in a document Chrome extension for scanning text without leaving the page it appears on API access for institutions screening submissions at scale	AI text detection with flagged sections Image, audio and video AI detection Fake PDF detector AI humanizer that rewrites to evade detection Paraphrasing, plagiarism checking and Chrome extension
Pros	One of the most established and widely recognized names in AI detection, with a large existing user base Combines AI detection with plagiarism and hallucination checks in a single workflow Free tier is usable for individual, lower-volume checks without a subscription	Detection across image, audio and video, not just text Fake PDF detection targets a real and growing fraud problem Free tier available before any payment
Cons	AI detection as a category carries an inherent false-positive risk on any tool, including this one Full-length document scanning beyond the free character limit requires a paid plan Recent acquisition introduces some uncertainty about how the standalone product evolves under Superhuman	Ships a humanizer for evading detection, with students among named users Submitting rewritten work is academic misconduct at most institutions No pricing figures published on the landing page
Company	GPTZero (Superhuman), founded 2023	Undetectable Inc.

Prices come from each vendor's pricing page, last checked 20260814. Check the vendor before you buy.

FAQ

Questions people ask

Is GPTZero better than Undetectable AI?

In our reviews GPTZero scores 4.4 and Undetectable AI scores 3.2. The better pick depends on the job. GPTZero: An AI detector built at Princeton that identifies LLM-generated text and now backs Superhuman's authenticity tools. Undetectable AI: Detects AI content across text, image, audio and video, and also rewrites text to evade detection.

Which is cheaper, GPTZero or Undetectable AI?

GPTZero: from $15/mo. Undetectable AI: free.

Do GPTZero and Undetectable AI have free plans?

Yes, both have a free plan.

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