Galileo

Galileo is a GenAI evaluation and observability platform using purpose-built Luna models to deliver 20+ quality metrics with low latency, plus production monitoring and guardrails, with free, $100/month Pro, and enterprise plans.

Galileo provides 'evaluation intelligence' for generative AI: a managed platform to measure output quality, monitor production behavior, and enforce runtime guardrails. Rather than relying solely on a large model to grade outputs, Galileo uses its own purpose-built Luna evaluation models, with the Luna-2 generation delivering 20+ metrics — including groundedness, completeness, correctness, and toxicity — at sub-200ms latency and lower cost than LLM-as-judge approaches. The platform spans the lifecycle: offline evaluation and experimentation during development, production observability with tracing, and guardrails that can block or flag risky outputs at runtime. A polished console ties these together with minimal setup, making it accessible to teams that don't want to build evaluation infrastructure themselves. Galileo was founded in 2021 by ex-Google and Apple engineers and has raised roughly $68M, with customers including HP, Twilio, Reddit, and Comcast. As of 2026 it offers a Free plan (5,000 traces/month, unlimited users and custom evals, no RBAC or advanced analytics), a $100/month Pro plan, and enterprise plans that add self-hosting and advanced controls.