Langfuse vs Braintrust 2026: Units of Trace Volume Against Units of Score
Quick verdict: Langfuse is our overall pick for langfuse vs braintrust.
- Best overall: Langfuse (4.3/5)
- Best free: Braintrust
- Best for teams: Langfuse
- Pricing last checked: 2026-10-03
Langfuse bills 100K trace units included on every paid tier from $29/mo; Braintrust bills scored outputs, 10K free then $2.50/1K, with the paid step at $249/mo.
| Tool | Rating | Pricing | Best for |
|---|---|---|---|
| Langfuse Best overall Best for teams | 4.3/5 | Free $29/mo (Core) | Langfuse is the open-source-first LLM observability platform: free Hobby with 50K units a … |
| Braintrust Best free | 4.2/5 | Free $249/mo (Pro) | Braintrust is the observability and eval platform with the most explicit score pricing in … |
Bottom line: Langfuse for a gradual price curve and self-hosting - $0, then $29, then $199, with unlimited users from the first paid step. Braintrust if you genuinely want to know your evaluation cost per 1,000 outputs, because no one else publishes that number, and your volume fits comfortably under 10K scores a month or your budget comfortably over $249. The decisive difference is the cliff: Langfuse raises the price gradually, Braintrust does not. Pick Arize AX for a $50 middle step.
Pricing and details
Langfuse · 4.3/5
Free plan available · $29/mo (Core)
Usage is billed in units (100K units included on paid tiers, then $8 per additional 100K, lower at volume); a separate self-hosted pricing page exists for on-prem deployments
No published annual rate; Pro carries an optional Teams add-on at $300/mo for SSO, SSO enforcement and fine-grained RBAC
Langfuse is the open-source-first LLM observability platform: free Hobby with 50K units a month, Core at $29/mo for 100K units and 90-day retention, Pro at $199/mo with three-year retention, Enterprise at $2,499/mo.
Score breakdown
Pros
- A real free tier with no credit card: 50K units a month, all platform features, 30 days of data access and 2 users
- Core at $29/mo is by far the cheapest paid step in the cluster, with unlimited users on every paid tier
- Cloud and self-hosted deployment from the same product, so privacy-sensitive teams have a real path instead of a sales call
- Published discounts for startups, research and students, plus a documented open-source project track
Cons
- Core retains data for 90 days only - three-year retention needs the $199 Pro plan
- No deployment runtime or autonomous debugging engine, so it covers tracing and evaluation but not the agent platform around them
- The optional Teams add-on for SSO and fine-grained RBAC is another $300/mo on top of Pro
Pricing verified 2026-10-03
Braintrust · 4.2/5
Free plan available · $249/mo (Pro)
Scored outputs are the billing unit (LLM-as-a-judge, autoevals, custom scorers) alongside processed data and model credits; retention beyond 30 days is billed at $0.50/GB/mo up to 180 days on Pro
No published annual rate; Pro offers 6-12 months free for qualifying startups
Braintrust is the observability and eval platform with the most explicit score pricing in the cluster: Starter is $0 with 10K scores a month, Pro jumps to $249/mo with 50K scores plus cheaper per-1K rates.
Score breakdown
Pros
- The most explicit pricing in the cluster: scores are named as the billing unit with rates ($2.50/1K on Starter, $1.50/1K on Pro), processed data and model credits are listed line by line
- Starter is genuinely free with unlimited users, projects, datasets, playgrounds and experiments - no card required
- Retention is priced rather than hidden: 14 days included on Starter, 30 on Pro, then $0.50/GB/mo up to 180 days
- 6-12 months free for qualifying startups, and an open research program with published foundations
Cons
- The Starter-to-Pro step is $0 to $249/mo, so a team that crosses 10K scored outputs a month faces a large step rather than a gradual bill
- Custom charts, environments, priority support and RBAC are Pro-only, so the free tier is genuinely basic
- No S3 data export or custom retention policies until Enterprise
Pricing verified 2026-10-03
Frequently asked questions
Which is better overall, Langfuse or Braintrust?
Langfuse is our overall pick (4.3/5 vs 4.2/5). Langfuse bills 100K trace units included on every paid tier from $29/mo; Braintrust bills scored outputs, 10K free then $2.50/1K, with the paid step at $249/mo.
Do Langfuse and Braintrust offer free plans?
Langfuse and Braintrust have a free tier. Langfuse paid plans start at $29/mo (Core); Braintrust paid plans start at $249/mo (Pro).
What does Langfuse cost?
$29/mo (Core) — Usage is billed in units (100K units included on paid tiers, then $8 per additional 100K, lower at volume); a separate self-hosted pricing page exists for on-prem deployments. Prices were last verified on 2026-10-03.