Former OpenSea Co-founder Leads AI Infrastructure Startup to $500M Valuation
OpenRouter, an AI infrastructure startup co-founded by former OpenSea CTO Alex Atallah, has raised $40 million in seed and Series A funding to scale its LLM aggregator platform. The round was led by Andreessen Horowitz and Menlo Ventures, with participation from Sequoia Capital and prominent angel investors.
The company is now reportedly valued at $500 million, reflecting strong investor confidence in its strategy to simplify AI model integration and inference routing for developers and enterprises.
What Is OpenRouter? An AI Model Aggregator for the Future
Founded in 2023, OpenRouter offers a unified API that aggregates access to hundreds of large language models (LLMs), including those from OpenAI, Anthropic, and Meta. It automatically routes user prompts to the best model available, based on cost, latency, accuracy, and privacy preferences.
“AI stacks are fragmenting. OpenRouter is unifying them with one API, one contract, and industry-leading uptime,” said a general partner at Andreessen Horowitz.
Developers use credits to pay for inferences, while OpenRouter takes a small per-request fee. The platform has quickly gained adoption as companies replace internal LLM gateways with OpenRouter’s streamlined system.
Rapid Growth and Adoption Across the Developer Ecosystem
Since launch, OpenRouter has scaled rapidly:
- Over $100 million in annualized inference spend, up from $10 million in late 2024.
- More than 1 million developers have used its API.
- Customers include startups and multinational corporations alike.
The platform integrates with popular developer tools like Microsoft VSCode, Zapier, and Cloudflare, making it easier for companies to deploy LLM-powered applications at scale.
Backed by Top Investors and AI Labs
OpenRouter’s close collaboration with leading AI labs has provided early access to cutting-edge models like GPT-4.1.
“Their diverse and active developer community has shared valuable feedback on how our models perform in practice,” said a technical lead from OpenAI.
This strategic partnership positions OpenRouter as a key infrastructure layer in the evolving AI model landscape, especially as inference costs become a major concern for businesses operating across multiple LLMs.
Atallah’s Vision: From NFTs to AI Infrastructure
Alex Atallah, who co-founded OpenSea in 2018, stepped away from the NFT marketplace in 2022 to pursue “zero-to-one” innovation in a new vertical. With OpenRouter, he aims to remove friction from LLM adoption, allowing developers to focus on domain-specific use cases rather than backend complexity.
“This round lets us keep shipping at the speed developers expect, while delivering uptime, privacy, and IT guarantees that enterprises demand,” Atallah said.