Together AI raises $800M at $8.3B valuation, plans 50x capacity growth

Together AI, the San Francisco-based open-source AI infrastructure platform, closed an $800 million Series C led by Aramco Ventures at an $8.3 billion post-money valuation—more than doubling its previous $3.3 billion valuation from February 2025. The round included Vista Equity Partners, General Catalyst, Emergence Capital, NVIDIA, and others.

The company reported annual bookings exceeded $1.15 billion last quarter as enterprises shift toward open-source models. Customers report inference cost savings of 6x to 60x compared to proprietary systems, with clients like Decagon cutting costs sixfold after migration. Together AI now serves thousands of paying customers including Cursor, Cognition, and Decagon.

Together AI will use the capital to expand inference products and scale its compute footprint roughly 50-fold over the next five years. The company has secured commitments for over 500 megawatts of compute capacity, independent of Together AI's own spending, signaling confidence from downstream infrastructure partners in the economics of open-model serving.

For architecture and capacity teams, Together's trajectory matters: annual bookings now track invoiceable monthly run rates above $95M, and the valuation arbitrage—enterprises paying 1/10th the token cost versus OpenAI or Anthropic for comparable model quality—is driving production adoption away from closed APIs. The 50x capacity target over five years is a credible demand signal in the neocloud market.