Baseten closes $1.5B Series F at $13B valuation, 20x revenue growth

Baseten, the San Francisco-based AI inference platform, raised $1.5 billion in Series F financing led by Altimeter Capital, Conviction, and Spark Capital, with Sands Capital and Wellington Management as co-leads. The round valued the company at up to $13 billion, tripling its $5 billion valuation from just five months prior. This marks Baseten's fourth fundraise in 18 months.

The inference platform processes more than 1 billion calls per day across 87 globally distributed clusters spanning 18 cloud providers. Revenue has grown approximately 20-fold year-over-year, and the company now counts leading AI companies including Cursor, Notion, Lovable, Harvey, and HubSpot among its customers.

Baseten builds systems software that manages GPU allocation, autoscaling, observability, billing, and developer tools for AI applications. Leading AI companies now allocate 30–50% of model spend toward custom and post-trained models optimized for specific workflows—exactly the use case Baseten's multi-model, multi-cloud infrastructure serves.

The capital will fund headcount expansion (the company is tripling staff in 2026), compute infrastructure investments, and enterprise sales acceleration. Baseten's growth trajectory reflects a fundamental market shift: as model capabilities commoditize, the bottleneck moves from training to running inference reliably and affordably at scale.