Superhuman Acquires AI Detection Company GPTZero

Superhuman has acquired GPTZero, the AI detection startup founded by Princeton graduate Edward Tian, the companies announced on Tuesday.

GPTZero began as Tian’s senior thesis project and grew into one of the most recognized AI-content detection platforms over the past three years. While financial details of the acquisition were not disclosed, Tian told Business Insider that the company had surpassed 19 million registered users and reached $30 million in annual recurring revenue.

The startup had already achieved profitability by 2024, according to Tian in an earlier interview with TechCrunch. Tian co-founded GPTZero alongside CTO Alex Cui, a longtime friend from high school. The company raised a total of $13.5 million in funding, including a $3.5 million seed round led by Uncork Capital and a $10 million Series A round in June 2024 led by Footwork co-founder Nikhil Basu Trivedi. Other investors included Reach Capital, Alt Capital, and Neo.

The acquisition brings GPTZero into Superhuman, the company that emerged after Grammarly acquired the email platform Superhuman last year and adopted its brand name. Although Superhuman already offered an AI detection feature within its platform, GPTZero has built its reputation around helping users identify AI-generated content and combat low-quality AI-produced material.

Grammarly’s own AI detection tools have primarily focused on helping users—particularly students—assess whether their writing appears to be AI-generated and make revisions when necessary. Addressing the rationale behind the acquisition, Superhuman stated that “two AI detectors are better than one,” suggesting that GPTZero’s technology will strengthen its existing AI detection capabilities.