Together AI raises $800 million and doubles its valuation to $8.3 billion

Led by Aramco Ventures, the Series C funding round is intended to finance infrastructure capacity that the company aims to increase fifty-fold over five years, driven by demand for inference on open models.

Together AI, a specialist in infrastructure for open source models, has closed an $800 million Series C round that brings its post-money valuation to $8.3 billion, more than double the previous level. The round is led by Aramco Ventures, along with Vista Equity Partners, General Catalyst, Emergence Capital, Nvidia, March Capital, Pegatron and SE Ventures.

The San Francisco-based company's value proposition is based on a cost comparison: by relying on open models such as DeepSeek, MiniMax or Kimi, its customers train and deploy their workloads for less than on the closed systems of OpenAI or Anthropic.

The money is to be used to expand the product range and above all to increase capacity: Together AI says it is aiming for an infrastructure footprint about fifty times larger within five years.