Braintrust Raises $80M at $800M Valuation for AI Eval Observability — New Free Starter Plan (March 2026) Makes Production LLM Evaluation Accessible

Braintrust Blog·medium signal

Braintrust closed an $80M Series B led by ICONIQ Capital, positioning as the observability layer for production AI. The platform connects dataset management, evaluation scoring, experiment tracking, and CI-based release enforcement in a single loop — every eval run links to exact prompt version, model, and dataset. The new Starter plan (March 2026) offers $0/month with 10K scores and 1GB included, then usage-based pricing, removing the barrier to entry for solo builders and small teams doing serious LLM evaluation.