Promptfoo
Latest round
- Series A
Last raised
- Jul 2025
Total raised
- $23M
Investors
- 2
About Promptfoo
Based in California, US, and founded in 2024 by Ian Webster and Michael D'Angelo, Promptfoo operates as a large language models testing company that develops open-source tools to help developers identify and address vulnerabilities in AI applications. Their core product offering includes an automated pentesting service designed to identify security, legal, and brand risks within LLM applications. Promptfoo provides custom probes targeting vulnerabilities of interest to developers, such as prompt injections and jailbreaks. The platform operates through a command-line interface for quick deployment and integration, serving over 25,000 developers worldwide, particularly in North America and Europe. Promptfoo generates revenue predominantly through a subscription-based model, offering tiered access to its LLM testing tools. Transactions typically involve annual or monthly subscriptions, priced to accommodate both small development teams and larger enterprises., Altimeter Capital, Amazon, Andreessen Horowitz, Anti Fund, Ark Invest, Bedrock, Blackstone, Boman Group, CalPERS - California Public Employees' Retirement System, Coatue Management, D1 Capital Partners, Dragoneer Investment Group, Fidelity Investments, Founders Fund, K2 Global, Khosla Ventures, Magnetar Capital, MGX, Microsoft, NVIDIA Corporation, Pengana Capital Group, Quiet Capital, SB Investment Advisers, Sequoia Capital, T Rowe Price, The Walt Disney Company, Thrive Capital, Tiger Global Management, Tioex Technologies, TPG, and Wisdom Ventures, agreed to acquire Promptfoo Inc. from Andreessen Horowitz and Insight Partners. Financial terms were not disclosed. The March 2026 acquisition will enable to incorporate Promptfoo’s technology into OpenAI Frontier so that businesses can evaluate agent actions, identify potential risks prior to launch, and keep documentation to facilitate oversight, governance, and accountability.
Who invested in Promptfoo
2 investors across 2 rounds
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Questions about Promptfoo
Who invested in Promptfoo?
Promptfoo has 2 investors on record across 2 venture rounds. Sign up free to see every VC on the cap table and the rounds they joined.
How much funding has Promptfoo raised?
Promptfoo has raised 2 venture rounds. Sign up free to see how much each round raised and the total.
When did Promptfoo last raise money?
Promptfoo's most recent round on record is a Series A, in Jul 2025.
What does Promptfoo do?
Based in California, US, and founded in 2024 by Ian Webster and Michael D'Angelo, Promptfoo operates as a large language models testing company that develops open-source tools to help developers identify and address vulnerabilities in AI applications.
Where is Promptfoo headquartered?
Promptfoo is headquartered in San Francisco, US.
Which VCs invest in companies like Promptfoo?
Among active investors with capital left to deploy, Andreessen Horowitz, Founders Fund, Accel and Thrive Capital back software companies at Promptfoo's stage. Their profiles are linked below.
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