Modal has raised $355 million in Series C funding at a $4.65 billion post-money valuation, after growing fivefold since September and surpassing $300 million in annualized revenue. The round was led by General Catalyst and Redpoint, with Menlo, Bain Capital Ventures, and Accel joining as new investors.
The company is building cloud infrastructure for AI workloads that do not fit neatly into traditional web application platforms. Modal supports use cases such as low-latency inference, dynamic agent runtimes, reinforcement learning, and large-scale batch jobs by pooling compute capacity across hundreds of data centers.
A major piece of its growth is coming from Sandboxes, Modal’s isolated environments for running AI-generated and untrusted code. The company said more than 1 billion sandboxes have been launched on the platform, and the product now accounts for more than a third of its revenue. That demand has grown as developers build coding agents, agentic commerce tools, reinforcement learning systems, and automated research workflows.
Modal plans to use the new funding to expand low-latency production inference, connect more of the model training and inference lifecycle, and scale its sandbox infrastructure to support millions of parallel environments. The company is also building more granular role-based access controls so customers can let AI agents execute code with tighter limits.
Cognition CEO Scott Wu said Modal supports both the company’s reinforcement learning infrastructure and production inference. “Millions of sandboxes on one end, real-time serving on the other. All on the same platform,” Wu said.