Pick Phoenix if
agent teams who will self-host Phoenix for $0 (uvx arize-phoenix serve) and only open Arize AX when they want a managed cloud.
Read the Phoenix pagePhoenix vs Promptfoo
Our take
Pick Phoenix if agent teams who will self-host Phoenix for $0 (uvx arize-phoenix serve) and only open Arize AX when they want a managed cloud. Pick Promptfoo if app teams who will run Community for $0 (MIT, self-host) and only buy Enterprise when they need SSO, a shared dashboard, and more than 10k probes.
Best for
Phoenix See why an agent failed and prove a fix
Promptfoo Fail the build before a prompt ships
Free plan
Phoenix $0 · local / Docker / Kubernetes. You bring compute. Homepage: uvx arize-phoenix serve
Promptfoo No free plan
Lowest paid
Phoenix AX Pro $50/mo
Promptfoo Not published by the vendor
Coding agent
Phoenix
Promptfoo Eval matrix
Runs where
Phoenix Hosted
Promptfoo Hosted
Watch out
Phoenix ELv2, not Apache
Promptfoo Community red team is 10k probes/month
Last checked
Phoenix 2026-10-22 · arize.com/pricing
Promptfoo 2026-10-22 · promptfoo.dev/pricing
Which one, then?
Pick Promptfoo if
app teams who will run Community for $0 (MIT, self-host) and only buy Enterprise when they need SSO, a shared dashboard, and more than 10k probes.
Read the Promptfoo page