GPTZero AI Detection Review (Acquired by Superhuman)

GPTZero is an artificial intelligence AI content detection tool co-founded by Edward Tian and Alex Cui in 2023, according to Business Insider.

Tian created GPTZero while studying at Princeton University to help users identify AI writing, following ChatGPT’s 2022 release, and it was launched in January 2023, as noted by a CBC article.

At Originality.ai, we launched a few months earlier, in November 2022 (before ChatGPT had launched), as the first commercial AI detector on the market.

When we first wrote this article, the GPTZero app was currently in beta mode. Three years later, let’s take a closer look at GPTZero in this updated review and see what’s changed since those early days.

Key Takeaways (TL;DR)

• GPTZero launched in early 2023 and was co-founded by Edward Tian and Alex Cui.
• The app was created in response to ChatGPT’s 2022 release.
• Originality.ai launched a few months earlier in November 2022, even before ChatGPT had launched.
• In June 2026, GPTZero was acquired by Superhuman (Grammarly).
• AI Detector By Originality.ai™ is the industry-leading alternative to GPTZero.

What Is GPTZero?

GPTZero is an AI detection app that launched in 2023 as a way to help users identify AI-generated text following the rapid rise of AI content with the November 30th, 2022, launch of ChatGPT.

In addition to AI detection, GPTZero also offers a variety of features to users, including plagiarism checks, hallucination detection, and grammar checking.

Just recently, in June 2026, GPTZero announced it was acquired by Superhuman (Grammarly), as noted by Business Insider. According to the article, both co-founders will be joining Superhuman as well.

At the time of the acquisition, GPTZero was valued at $88 million and reported that it had over 19 million users with $30 million in annual recurring revenue (ARR).

Why are AI detectors important in 2026?

As AI content creation is becoming increasingly common, it is up to AI detectors to help users establish transparency about how something was written. This has applications across industries, from content marketing to education and business.

A look back at GPTZero’s beginnings

On January 2nd, Edward Tian posted about building GPTZero on social media:

Here’s what the GPTZero homepage looked like the next day on January 3rd, 2023:

… and then on January 9th, 2023, just a few days after its launch:

When this article was initially published, here’s what the GPTZero app looked like:

In June 2023, we also shared a video review of the GPTZero tool:

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Now, here’s what it looks like today (June 23rd, 2026):

How Does GPTZero Work?

According to GPTZero, their method of AI detection takes input text and then uses deep learning, a sentence classifier, and a paraphrase shield to help identify the origins of the text.

Shortly after GPTZero was launched, they published an article in March 2023, outlining that their AI detection model analyzed text based on perplexity and burstiness.

Perplexity refers to the randomness of a text to a model. It examines how good a language model (like ChatGPT) is at predicting the next words. Higher scores indicate unpredictability, implying that a text is human-made. Initially (when this article was first published), GPTZero based perplexity on the GPT-2 model.

Burstiness refers to how uniform or constant the perplexity is over time compared to varied human-written text. This metric looks at the distribution of sentences and determines whether there is uniformity or pattern. It’s based on the idea that humans tend to mix short and long sentences when writing.

To learn more about how the Originality.ai AI detector works, check out our guide and accuracy study.

GPTZero Alternatives

While GPTZero is a popular AI detection tool, it’s not the only AI detector on the market.

Let’s take a closer look at some alternatives, including our AI Detector By Originality.ai™.

AI Detector By Originality.ai™

AI Detector By Originality.ai™ is the industry-leading alternative to GPTZero.

Originality.ai was the first commercial AI detector, launched in November 2022 (before ChatGPT), and was founded by Jon Gillham, CEO of Originality.ai. 

Seeing as we showed GPTZero back in the day earlier in this article, we felt it was only fair to show Originality.ai when it launched; this snapshot is from November 26, 2022.

And here’s what Originality.ai looks like today (June 23, 2026):

Originality.ai has 99% accuracy and has proven accuracy across multiple third-party studies.

Originality.ai vs. GPTZero Accuracy in 3rd-Party Studies published in 2025 and 2026:

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To read a more extensive overview of independent, third-party studies, visit our meta-analysis.

Originality.ai also offers users a complete, patented content quality toolkit. The Originality.ai patent covers our all-in-one text analysis and verification system that checks for AI content, plagiarism, factual accuracy, readability, and spelling and grammar.

Other AI Detection tools to consider

That being said, GPTZero and Originality.ai aren’t the only two AI detection tools available.

Other AI detection options that users might consider include:

• Winston AI (gowinston.ai)
• Turnitin
• Grammarly (Superhuman has now acquired GPTZero)
• ZeroGPT

Read our round-up blog post on AI detection tools for even more insights.

Final Thoughts

GPTZero is an effective AI detector and a competitive option for users looking to identify AI-generated text.

With Superhuman’s (Grammarly) recent acquisition of the tool, it will be interesting to see how GPTZero continues to evolve as part of the broader Superhuman platform.

The acquisition of GPTZero by Superhuman is a notable milestone in the AI detection industry, highlighting that AI detection is becoming integral to the editing and content review process across industries.

If you’re looking for an alternative to GPTZero, consider the industry-leading AI Detector By Originality.ai™, with exceptional accuracy as demonstrated by independent, 3rd-party studies.

At Originality.ai, we continue to focus on AI Detection and providing users with a comprehensive suite of tools to publish and submit content with integrity and confidence.

Further Reading:

• AI Accuracy Study
• Meta-analysis of Studies
• How Does AI Detection Work?

FAQs

What is GPTZero?

GPTZero is an AI detector that enables users to scan writing to find out whether it was created by generative AI or if it was human-written.

Who founded GPTZero?

GPTZero was co-founded by Edward Tian and Alex Cui in 2023.

When did GPTZero launch?

GPTZero launched on January 2, 2023 in a social media post by Edward Tian. You can check out a screenshot of the GPTZero website on launch day through the Internet Archive’s Wayback Machine.GPTZero launched on January 3, 2023. You can check out a screenshot of the GPTZero website on launch day through the Internet Archive’s Wayback Machine.

When was GPTZero acquired by Superhuman (Grammarly)?

GPTZero announced that it was acquired by Superhuman (Grammarly) on June 23, 2026.

What’s the alternative to GPTZero?

There are plenty of alternatives to GPTZero’s AI detector. AI Detector By Originality.ai™ is an industry-leading GPTZero alternative that has demonstrated high accuracy in independent third-party studies.