- Modal raised $750M at a $15.75B valuation, led by Accel, with Kleiner Perkins joining.
- The valuation is more than three times the $4.65B set in its May 21 Series C.
- Its run rate passed $1B, and its Sandboxes product alone reached $300M.
Erik Bernhardsson helped build Spotify’s music recommendations, then spent six years as CTO of Better.com, and came away convinced the cloud held developers back. On October 14, the company he founded in 2021, Modal, said it had raised $750M at a $15.75B valuation, led by Accel, less than five months after it was valued at $4.65B.
Kleiner Perkins joined the round, and all of Modal’s existing investors took part, including Menlo Ventures, General Catalyst, Redpoint, Lux Capital, and Bain Capital Ventures.
Modal said usage has tripled since its Series C, has grown more than 15x year on year, and its annualised run rate has crossed $1B.
Bernhardsson’s pitch starts with scarce graphics processing units (GPUs) and large AI models that are slow to load. Developers can work around both on older tools, he wrote, “but you end up in YAML hell and GPU procurement purgatory.”
The sandbox business behind the run rate
Modal, founded in 2021, pools computing capacity from more than 20 cloud providers into one network and lets developers run code on it without managing servers. It built its own file system, container runtime, scheduler, and networking to do that, and it does not run its own data centres.
The sharpest growth is in Sandboxes. Modal launched the product in 2023, when developers began using large language models to write code that needed somewhere isolated to run.
For example, a coding assistant can test a script it just wrote inside a sandbox, away from the customer’s own systems. Sandboxes have since reached a $300M run rate, just under a third of the total, with close to 3 billion sandboxes launched and capacity for 1 million running at once.
Customers include DoorDash, whose AI platform team uses Modal to move apps from experiment to production, Cognition, Ramp, Linear, and Hebbia, which build background agents on it. Runway generates video there, while Physical Intelligence, Generalist AI, and 1X train robots.
Modal says TypeSafe AI’s Jev, which it calls one of the fastest-growing products ever, served 1 trillion tokens, the chunks of text a model reads and writes, on the platform in its first three days.
Bernhardsson, who created the open-source Annoy library for search and recommendations, is chief executive. Co-founder Akshat Bubna, an early engineer at Scale AI, is chief technology officer. Modal has more than 200 staff across New York, San Francisco, and Stockholm, up from more than 120 at the time of the Series C.
How fast the price moved
Modal was valued at $1.1B in September 2025, when it raised an $87M Series B led by Lux Capital. Its $355M Series C followed on May 21 at $4.65B, led by General Catalyst and Redpoint. The Series D at $15.75B is more than 14 times the Series B figure in just over a year.
The Series C came in two tranches, Reuters reported: the first at a $2.5B valuation, the second at $4.65B once more investors came calling. Accel and Menlo Ventures were in the second tranche, so Accel went from first-time investor at $4.65B to leading this round at $15.75B. Modal has raised roughly $1.2B across its disclosed rounds, including a seed round led by Amplify Partners and a $16M Series A in October 2023.
Two investors weighed in on X. Mamoon Hamid, a partner at Kleiner Perkins, wrote that every serious AI team his firm talks to eventually says the same thing: “We run it on Modal.” Lux Capital partner Grace Isford, whose firm led the Series B, wrote that Modal “radically reimagined a seamless developer experience” from the start.
A crowded race for inference
The money is chasing a market that has changed shape. Gartner forecasts worldwide spending on AI-optimised infrastructure-as-a-service of $42B in 2026, up 96%, and expects inference, the running of trained models, to account for $23.3B of it, ahead of $19B for training.
Rivals are raising just as fast. Baseten took $300M at a $5B valuation in January, then a $1.5B Series F at $13B on June 22. Bloomberg reported on September 23 that Baseten and Modal were both in talks to at least double their valuations, with Baseten’s talks at $26B. Together AI raised $800M at $8.3B on July 1, led by Aramco Ventures, and said its annual bookings passed $1.15B in the prior quarter. Fireworks AI raised $1.505B at $17.5B on July 16 and reports a run rate above $1B.
Modal’s valuation is no more than about 16 times its run rate. Fireworks sits at no more than about 17.5 times, and Together AI at roughly seven times its bookings, though the two measures are not the same. While Together AI and Fireworks centre on running and customising open models, Modal describes itself as a set of building blocks, from functions to Sandboxes to training, that developers combine themselves.
The number to watch is Sandboxes. If AI agents keep writing code that needs a safe place to run, a product launched in 2023 could carry more of Modal’s valuation than GPU rental ever did. If the biggest clouds or the model makers build their own sandboxes, a multiple near 16 will be hard to defend.
