Langfuse vs PromptLayer

Two fact sheets from our own research, side by side — pricing, platforms, API access and status re-checked by us rather than quoted from the vendors.

The short answer

Cheaper paid plan: Langfuse — $29/mo vs $49/mo for PromptLayer
Free plan: Both have one
Public API: Both have one
Higher Trust score: PromptLayer — 92 vs 80 for Langfuse
Best fit: Langfuse: Engineering teams running LLM apps or agents in production who need traces and cost tracking · PromptLayer: Teams letting PMs, content or domain experts edit production prompts without a deploy

From our own records as of each tool's last check. Anything we have not confirmed is left out rather than guessed. How we verify

LangfuseOpen-source LLM engineering platform for tracing agents, versioning prompts, running evals and tracking cost, hosted or self-hosted.

PromptLayerPrompt versioning, evals and tracing for LLM engineering teams

Side by side

Fact	Langfuse	PromptLayer
Category	LLM Observability & Evaluation	Prompt Management & Versioning
Pricing model	Freemium	Freemium
Starts at	$29/mo	$49/mo
Public API	Yes	Yes
Trust score	80 / 100	92 / 100
Platforms	Web, API	Web, API
Company	Langfuse GmbH	Magniv, Inc.
Launched	2023	—
Last verified	Oct 29, 2026	Oct 16, 2026

What our research says

Langfuse

Langfuse is a strong default for teams that want tracing, prompt versioning and evaluations in one open-source tool, with the option to keep data on their own infrastructure. Teams that only want a hosted logging proxy with no SDK work, or that need guaranteed enterprise SSO without paying for add-ons, may find simpler or more bundled options.

Pros

MIT-licensed core that can be self-hosted without usage limits
Covers tracing, prompt management, evaluation and dashboards in one product
Generous free cloud tier and unlimited users from the $29 Core plan
OpenTelemetry support and SDKs for Python and JavaScript

Cons

Usage above the included 100k units is billed extra, so busy apps pay more than the headline price
Free tier keeps only 30 days of data and two users
Enterprise SSO and RBAC require the $300 Teams add-on on Pro or the Enterprise plan

PromptLayer

The right pick when the people who actually own your prompt wording are product or domain experts rather than engineers; if prompts live in git and only engineers touch them, Langfuse or Braintrust cover the same ground with less product surface.

Pros

Visual prompt editing plus deployment approvals is a genuine differentiator over log-only observability tools
Free tier includes 5 users and eval executions, not just request logging
Prompts are fetched at runtime via SDK or REST, so no redeploy is needed to change one
HIPAA with BAA and flexible hosting are offered on enterprise, which most prompt tools skip

Cons

The jump from Pro at $49/month to Team at $500/month is a tenfold step with no tier between
Free tier caps at 2,500 requests/month, which a modest production app exhausts quickly
Runtime prompt fetching puts a third party in your request path unless you cache
Crowded category — Langfuse, Braintrust and LangSmith all overlap heavily

Which one fits

Choose Langfuse if you need

Engineering teams running LLM apps or agents in production who need traces and cost tracking
Organisations that must self-host observability data for compliance
Teams that want prompts, datasets and evals tied to the same traces

Choose PromptLayer if you need

Teams letting PMs, content or domain experts edit production prompts without a deploy
Regression-testing prompt changes against a labelled dataset before rollout
Tracing a bad production output back to the exact prompt version and cost