Pick Guardrails AI if
app teams who will self-host validators (or already have a model endpoint) and want a Hub instead of writing every regex.
Read the Guardrails AI pageGuardrails AI vs Promptfoo
Our take
Pick Guardrails AI if you're on a app team who will self-host validators (or already have a model endpoint) and want a Hub instead of writing every regex. Pick Promptfoo if you're on a app team 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. Skip Guardrails AI if you're buyers who want a quoted enterprise prompt firewall with a
Best for
Guardrails AI Fail a bad completion before it ships
Promptfoo Fail the build before a prompt ships
Free plan
Guardrails AI $0 · license. You pay compute
Promptfoo No free plan
Lowest paid
Guardrails AI Not published by the vendor
Promptfoo Not published by the vendor
Coding agent
Guardrails AI
Promptfoo Eval matrix
Runs where
Guardrails AI Hosted
Promptfoo Hosted
Watch out
Guardrails AI You run it
Promptfoo Community red team is 10k probes/month
Last checked
Guardrails AI 2026-10-28 · github.com/guardrails-ai/guardrails
Promptfoo 2026-10-27 · 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