Braintrust
Eval-first AI platform with Brainstore DB and Loop auto-optimizer for prompts
What is Braintrust?
Braintrust is an AI evaluation and observability platform that combines real-time trace inspection, automated scoring via LLM-as-judge or code, and production-to-test-dataset workflows. Teams convert live traces into regression datasets, run eval experiments, and use the Loop agent to auto-optimize prompts and datasets. It runs on Brainstore, a purpose-built database for AI traces that the company claims accelerates full-text search and span loading versus general-purpose stores.
Knowledge bases, internal search, operations, data, finance, HR, and back-office tools with AI workflows.
See the full Knowledge & Ops guide to compare more tools, buyer criteria, and related workflows.
Use cases to evaluate
Turn yesterday's flagged production traces into a regression suite before changing a prompt
Run LLM-as-judge graders on 1K-prompt datasets to compare GPT-4 vs Claude vs Llama
Let Loop iterate on prompt variants overnight and surface the best variant by score
Trace multi-step agent runs with tool calls, then attach human review scores per span
Fit to evaluate
Applied AI teams at scaleups that already write evals and want to automate them
ML platform leads picking the eval/observability stack for a 20+ engineer org
Product teams shipping LLM features who need a kill switch backed by graded experiments
Companies in regulated industries that need BAA, SAML SSO, and self-hosted options
Business fit
Right for you if evals are the bottleneck on shipping AI changes and you want one place to write graders, replay production traces, and grade experiments before promoting a prompt or model. Skip if you mostly need cost dashboards rather than rigorous eval pipelines, or if your team won't invest in writing scoring functions. Used by Vercel, Notion, Coursera, Dropbox, and Replit, which signals it scales to serious AI product orgs. The Loop agent is worth piloting if you're tired of hand-tuning prompts on every model release.
How to evaluate Braintrust
Use this category when operational data, policies, tasks, or internal requests are spread across disconnected systems.
Confirm the exact workflow
Map Braintrust to one concrete workflow first, such as turn yesterday's flagged production traces into a regression suite before changing a prompt. Avoid buying before the owner, trigger, output, and success metric are clear.
Check category fit
Compare internal search, permissions, workflow support, and reporting.
Compare practical alternatives
Shortlist Braintrust against Glean, Guru, Slite so the decision is based on fit, effort, and workflow ownership rather than brand recognition alone.
Validate cost and rollout effort
Starter free with 1GB processed data, 10K scores, 14-day retention; Pro $249/month covers 5GB data, 50K scores, 30-day retention, S3 export, MFA; overages $3/GB and $1.50 per 1K scores on Pro; Enterprise custom with RBAC, SAML SSO, BAA, on-prem. Also confirm implementation time, support needs, and whether the medium setup matches your team.
Compare Braintrust with alternatives
Use this quick comparison before booking demos or moving data into a new system.
| Primary workflow | Turn yesterday's flagged production traces into a regression suite before changing a prompt, Run LLM-as-judge graders on 1K-prompt datasets to compare GPT-4 vs Claude vs Llama |
|---|---|
| Best-fit team | Applied AI teams at scaleups that already write evals and want to automate them, ML platform leads picking the eval/observability stack for a 20+ engineer org |
| Implementation effort | Medium setup and maintenance profile |
| Pricing check | Free plan + paid plans |
| Closest alternatives | GleanGuruSliteSlab |
Braintrust pricing
| Model | Free plan + paid plans |
|---|---|
| Snapshot | Starter free with 1GB processed data, 10K scores, 14-day retention; Pro $249/month covers 5GB data, 50K scores, 30-day retention, S3 export, MFA; overages $3/GB and $1.50 per 1K scores on Pro; Enterprise custom with RBAC, SAML SSO, BAA, on-prem. |
| Checked |
Common questions about Braintrust
What is Braintrust?
Braintrust is an AI evaluation and observability platform that combines real-time trace inspection, automated scoring via LLM-as-judge or code, and production-to-test-dataset workflows. Teams convert live traces into regression datasets, run eval experiments, and use the Loop agent to auto-optimize prompts and datasets. It runs on Brainstore, a purpose-built database for AI traces that the company claims accelerates full-text search and span loading versus general-purpose stores.
What is Braintrust used for?
Common use cases: Turn yesterday's flagged production traces into a regression suite before changing a prompt; Run LLM-as-judge graders on 1K-prompt datasets to compare GPT-4 vs Claude vs Llama; Let Loop iterate on prompt variants overnight and surface the best variant by score; Trace multi-step agent runs with tool calls, then attach human review scores per span.
How much does Braintrust cost?
Starter free with 1GB processed data, 10K scores, 14-day retention; Pro $249/month covers 5GB data, 50K scores, 30-day retention, S3 export, MFA; overages $3/GB and $1.50 per 1K scores on Pro; Enterprise custom with RBAC, SAML SSO, BAA, on-prem.
Who is Braintrust best for?
Braintrust fits Applied AI teams at scaleups that already write evals and want to automate them, ML platform leads picking the eval/observability stack for a 20+ engineer org, Product teams shipping LLM features who need a kill switch backed by graded experiments, Companies in regulated industries that need BAA, SAML SSO, and self-hosted options. Right for you if evals are the bottleneck on shipping AI changes and you want one place to write graders, replay production traces, and grade experiments before promoting a prompt or model. Skip if you mostly need cost dashboards rather than rigorous eval pipelines, or if your team won't invest in writing scoring functions. Used by Vercel, Notion, Coursera, Dropbox, and Replit, which signals it scales to serious AI product orgs. The Loop agent is worth piloting if you're tired of hand-tuning prompts on every model release.
What are alternatives to Braintrust?
Common alternatives to Braintrust include Glean, Guru, Slite, Slab, Tettra, Sana.