Langfuse

Open-source platform for tracing LLM applications, running evaluations and versioning prompts, as a cloud service or self-hosted.

By Langfuse GmbH (ClickHouse) · langfuse.com

Package download activity

Each package is shown on its own; packages that can be installed together are never added up. Week 2026-W40 (2026-09-28 to 2026-10-04).

npm@langfuse/tracing · headline (ranked)

3,268,181 downloads in the week, +12.2% vs prior week · rank 2 on npm

2026-W29 to 2026-W40, 12 weeks; min 1,202,447, max 3,268,181

npm@langfuse/otel · current

2,858,525 downloads in the week, +10.3% vs prior week

2026-W29 to 2026-W40, 12 weeks; min 1,355,462, max 2,858,525

npmlangfuse · legacy

2,410,420 downloads in the week, +21.6% vs prior week

2026-W29 to 2026-W40, 12 weeks; min 1,347,862, max 2,410,420

PyPIlangfuse · headline (ranked)

6,306,471 downloads in the week, +12.7% vs prior week · rank 3 on PyPI

2026-W29 to 2026-W40, 12 weeks; min 4,867,665, max 6,662,886

Cross-check 2026-W40 vs PyPI Stats (mirrors excluded): within 5% (+0.57%). PyPI Stats query

langfuse/langfuse: 35,491 stars (rank 2). Stars are a point-in-time count of a repository's bookmarks, not people using the tool.

Series starts 2026-W40 (35,491).

Facts for Langfuse
Categories	Tracing & observability, Evaluation, Prompt management
Status	Generally available
Licence	MIT (open core)	source, checked 2026-10-07
Self-host	Yes	source, checked 2026-10-07
OpenTelemetry	Native (OTLP)	source, checked 2026-10-07
Pricing model	usage
Entry price	$29/mo; Core cloud plan, 100k units/month included then $8/100k units; Hobby is free (50k units/month); self-hosting is a separate free option	source, checked 2026-10-07
Free tier	Yes
Measurability	Measured (mapped SDK packages)

Facts last verified 2026-10-07 on first-party pages. Prices as published, taxes excluded; non-USD prices are not converted.

Spotted an outdated fact? The methodology page explains how facts are checked; corrections are applied at the next weekly build.