OpenAI acquires Promptfoo to secure its AI customers

OpenAI announced Monday that it has acquired Promptfoo, an AI security startup founded in 2024 to protect MBAs from online adversaries.

Once the deal closes, Promptfoo’s technology will be integrated into OpenAI Frontier, the enterprise platform for AI clients, Frontier Lab said in a blog post.

The development of autonomous AI agents that perform digital tasks has generated excitement about productivity gains. But it also gives bad actors new opportunities to access sensitive data or manipulate automated systems. This deal underscores how Frontier Laboratories is seeking to demonstrate that its technology can be used safely in critical business processes.

Promptfoo was founded by Ian Webster and Michael D’Angelo to develop tools that companies can use to test vulnerabilities in LLMs, including an interface and an open source library. The company reports that its products are used by more than 25% of Fortune 500 companies.

Promptfoo has raised just $23 million since its founding and was valued at $86 million after its last round in July 2025, according to PitchBook. OpenAI did not disclose the value of the deal.

The OpenAI post said Promptfoo’s technology will allow its agent platform to perform automated red teaming, evaluate agent workflows for security concerns, and monitor activities related to risk and compliance needs. The company also said it expects to continue building out Promptfoo’s open source offering.