Alternatives to Langfuse
Open-source LLM engineering platform for tracing, evals, and prompt management.
Langfuse ranks #2 of 8 in AI evaluation platforms, with an Alt Score of 100. It is licensed under MIT, open source with paid hosting from $29/month (USD) and available on the web. 13 of 13 checklist rows are verified against a public source.
Langfuse is an open-source LLM engineering platform providing tracing, prompt management, evaluations, datasets, and analytics for LLM applications; self-hostable or cloud.
AI engineering teams building LLM applications and agents who need observability, evaluation, and prompt management — from solo developers on the free Hobby cloud tier to enterprises wanting a self-hosted, data-sovereign deployment. It works with any LLM stack via OpenTelemetry-based SDKs and framework integrations (LangChain, LlamaIndex, Haystack, LiteLLM, Vercel AI SDK, and more).
A unified LLM engineering platform covering application tracing and observability, prompt management (versioning, labels, a side-by-side playground, A/B testing via labels), evaluation (LLM-as-a-judge, code evaluators, human annotation queues, datasets and experiments including CI/CD gating), and metrics (custom dashboards, cost/token tracking, monitors and alerts on Cloud). Core product capabilities are MIT-licensed with no usage limits; a few enterprise-only modules (SCIM, audit logging, data retention policies) require a commercial license when self-hosting.
Developers instrument their app with the Langfuse Python or JS/TS SDK (built on OpenTelemetry) or a native framework integration to send traces to either Langfuse Cloud or a self-hosted instance run via Docker Compose, Kubernetes/Helm, or Terraform on AWS/Azure/GCP. From there, teams manage and version prompts, run automated or human evaluations against datasets, gate releases with CI/CD experiments, and monitor cost, quality, and latency through dashboards and the metrics API.
Where Langfuse stands out
Verified capabilities most alternatives don't have.
Why people leave Langfuse
Dashed reasons are sourced facts; the rest are opinions. Vendors can dispute.
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Ranked alternatives
Ordered by Alt Score. Click any score to see the breakdown.
Opik is an open-source LLM evaluation platform from Comet for tracing, evaluating, and monitoring LLM applications, with datasets, LLM-as-judge metrics, and a prompt playground.
Phoenix is an open-source observability and evaluation library from Arize AI for tracing, evaluating, and troubleshooting LLM applications, built on OpenTelemetry.
Braintrust is an evaluation and observability platform for AI products, with datasets, LLM-as-judge scorers, prompt playground, and production logging.
HoneyHive is an AI evaluation and observability platform for testing, tracing, and monitoring LLM applications, with datasets, LLM-as-judge evaluators, and human review.
LangSmith is a platform for debugging, testing, evaluating, and monitoring LLM applications, with tracing, datasets, and LLM-as-judge evaluations.
Weave is the Weights & Biases toolkit for tracking, evaluating, and monitoring LLM applications, with tracing, scorers, and experiment comparison.
Feature comparison
Rows come from the AI evaluation platforms checklist (17 rows). Human-verified cells only. ? means the value has not been verified.
| AI evaluation platforms checklist | Langfuse | Comet Opik | Arize Phoenix | Braintrust | HoneyHive | LangSmith |
|---|---|---|---|---|---|---|
| Pricing model | ||||||
| Starts at | ||||||
| License | ||||||
| Platforms | ||||||
| Open source | ||||||
| Self-hostable | ||||||
| Tracing / observability | ||||||
| Prompt playground & versioning | ||||||
| Dataset management | ||||||
| LLM-as-judge evals | ||||||
| Human annotation / review | ||||||
| Online (production) monitoring | ||||||
| A/B experiments | ||||||
| CI / regression testing | ||||||
| Cost & token tracking | ||||||
| Framework-agnostic SDK | ||||||
| Free tier |
Every fact and feature listed for Langfuse is verified against its own pages. Each alternative is sourced on its own page.
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Pricing model OSS + paid hosting verified 2026-07-17
Get started on the Hobby plan for free. No credit card required. Langfuse Cloud (we host) Self-hosted (you host)
https://langfuse.com/pricing -
Starts at $29/month (USD) verified 2026-07-17
Cheapest paid Langfuse Cloud tier (Core). The Hobby cloud tier and self-hosting are free.
Core For production projects. Longer data access and unlimited users. $29 / month
https://langfuse.com/pricing -
Platforms Web verified 2026-07-17
Accessed via web app (cloud or self-hosted); Python/JS SDKs are not part of the platforms enum.
Langfuse Web: The main web application serving the Langfuse UI and APIs.
https://langfuse.com/self-hosting -
Status active verified 2026-07-17
Langfuse is growing fast (we doubled the team in the last 6 months) - since January 2026 we're part of ClickHouse, we're hiring engineering hybrid across the EU.
https://raw.githubusercontent.com/langfuse/langfuse/main/README.md -
License MIT verified 2026-07-17
MIT Expat" license as defined below." — Core platform is MIT licensed; code under ee/, web/src/ee/, worker/src/ee/ directories is licensed separately under ee/LICENSE (Enterprise Edition modules like SCIM, audit logging, data retention poli
Content outside of the above mentioned directories or restrictions above is available under the
https://raw.githubusercontent.com/langfuse/langfuse/main/LICENSE -
Open source Yes verified 2026-07-17
All product capabilities—tracing, evaluations, prompt management, experiments, annotation, the playground, and more—are MIT licensed without any usage limits.
https://langfuse.com/docs/open-source -
Self-hostable Yes verified 2026-07-17
Langfuse is open source and can be self-hosted using Docker. This section contains guides for different deployment scenarios.
https://langfuse.com/self-hosting -
Tracing / observability Yes verified 2026-07-17
The core of this is application tracing — structured logs of every request that capture the exact prompt sent, the model's response, token usage, latency, and any tools or retrieval steps in between.
https://langfuse.com/docs/observability/overview -
Prompt playground & versioning Yes verified 2026-07-17
Playground confirmed separately: 'Test and iterate on your prompts directly in the Langfuse Prompt Playground' (https://langfuse.com/docs/prompt-management/features/playground).
Each prompt version is automatically assigned a version ID. Additionally, you can assign labels to follow your own versioning scheme.
https://langfuse.com/docs/prompt-management/features/prompt-version-control -
Dataset management Yes verified 2026-07-17
A dataset is a collection of inputs and expected outputs and is used to test your application.
https://langfuse.com/docs/evaluation/experiments/datasets -
LLM-as-judge evals Yes verified 2026-07-17
LLM-as-a-Judge is an evaluation methodology where an LLM is used to assess the quality of outputs produced by another LLM application.
https://langfuse.com/docs/evaluation/evaluation-methods/llm-as-a-judge -
Human annotation / review Yes verified 2026-07-17
Annotation Queues are a manual evaluation method which is built for domain experts to add scores and comments to traces, observations or sessions.
https://langfuse.com/docs/evaluation/evaluation-methods/annotation-queues -
Online (production) monitoring Yes verified 2026-07-17
Monitors are noted as 'available on Langfuse Cloud only'; self-hosted deployments still get production tracing, metrics API and custom dashboards per the Metrics overview page.
Monitors allow you to catch cost and quality issues before they impact your users. You can receive notifications over Slack, trigger GitHub Actions, or call your own Webhooks.
https://langfuse.com/docs/metrics/features/monitors -
A/B experiments Yes verified 2026-07-17
Langfuse Prompt Management enables A/B testing by allowing you to label different versions of a prompt (e.g., prod-a and prod-b). Your application can randomly alternate between these versions, while
https://langfuse.com/docs/prompt-management/features/a-b-testing -
CI / regression testing Yes verified 2026-07-17
Use Langfuse experiments in your CI/CD pipeline to catch quality regressions before they ship.
https://langfuse.com/docs/evaluation/experiments/experiments-ci-cd -
Cost & token tracking Yes verified 2026-07-17
Langfuse tracks the usage and costs of your LLM generations and provides breakdowns by usage types.
https://langfuse.com/docs/observability/features/token-and-cost-tracking -
Framework-agnostic SDK Yes verified 2026-07-17
README also lists native integrations for LangChain, LlamaIndex, Haystack, LiteLLM, Vercel AI SDK, Mastra, and more.
Based on OpenTelemetry , so you can use any OTEL-based instrumentation library for your LLM stack.
https://langfuse.com/docs/sdk -
Free tier Yes verified 2026-07-17
Hobby Get started, no credit card required. Great for hobby projects and POCs. Free
https://langfuse.com/pricing
FAQ
Yes. Arize Phoenix, Braintrust and HoneyHive have a free tier or are fully free. Free-tier limits in the comparison table are verified and dated.
Comet Opik, Arize Phoenix and Braintrust — every license claim links its source.