Synthetic User Startup Simile Raises $200 Million at $2 Billion Valuation

AI startup Simile has joined the unicorn club after raising $200 million in a Series B round just five months after its $100 million Series A and emergence from stealth.

The round values the company at $2 billion, according to Simile.

Greenoaks led the Series B, with participation from Index Ventures, Hanabi, Bain Capital Ventures, A*, Factory, Definition, and CVS Health Ventures.

CVS is also one of Simile’s key enterprise customers.

AI-generated users for research and testing

Simile builds AI-generated synthetic users to help companies run product research, marketing analysis, and customer testing without relying entirely on traditional surveys.

The company was founded by Stanford PhD graduate Joon Sung Park, whose research included “Smallville,” a project where AI agents simulated daily human life, forming relationships and social behaviours.

That work has evolved into Simile’s commercial platform for creating virtual users to support business decision-making.

Long-term simulation ambitions

Simile’s long-term goal is to simulate “all eight billion people on earth, accurately and honestly.”

While highly ambitious, the idea of synthetic users is gaining traction as companies explore AI-driven customer insights for product development and research.

The approach allows businesses to test ideas and prototypes quickly, similar to how AI coding tools help developers build and evaluate software faster.

Rising interest in synthetic user startups

Simile is part of a growing group of startups in this space.

Another company, Aaru, raised a Series A in December at a reported $1 billion valuation for its own AI-generated research participants.

The momentum around Simile and similar companies reflects increasing investor belief that synthetic users could become a key tool for marketing, product design, and research, alongside traditional consumer feedback.