Langfuse is the most used open-source LLM engineering platform

Teams use Langfuse for observability, evaluation, and prompt management of LLM applications and agents. This page collects the public metrics behind the claim. Most numbers below are live and refresh automatically.

50,000+

Companies

90B+

Observations / month

65M+

SDK installs / month

38M+

Docker pulls

Of the Fortune 50

129

Of the Fortune 500

37,014

GitHub stars

100+

Integrations

SDK downloads

Langfuse has the most downloaded SDKs among LLM observability and evaluation platforms on both PyPI and npm.

	PyPI downloads / month	npm downloads / month
🪢 Langfuse
MLflow
Pydantic Logfire
Braintrust
Opik (Comet)
Arize Phoenix

Live via shields.io. Packages: langfuse and @langfuse/tracing, mlflow and mlflow-tracing, logfire, braintrust, opik, arize-phoenix-otel and @arizeai/phoenix-otel.

GitHub stars

Langfuse is the most starred open-source LLM engineering platform on GitHub.

Source: star-history.com

Customers

Teams at Canva, Khan Academy, Merck, and many more run Langfuse in production.

"We wanted something built for agents as users first. And that means API first. An agent should never get stuck waiting for a human because of a deficiency in the API. This is what Langfuse is."

David Traina

Data Platform at Ramp

"Langfuse hits the sweet spot between engineering requirements and empowerment of non-technical users to contribute their domain expertise."

Andreas Schuster

Head of Product, AI Help Experience at Canva

"Langfuse has enabled our developers to get extremely fast feedback. It's fundamental to how our developers understand their AI implementations."

Walt Wells

Staff Software Engineer at Khan Academy

"The whole pipeline to improve our chat agent happens entirely in Langfuse. Engineers and domain experts work hand-in-hand."

Laurenz Hemmen

Machine Learning Scientist at DKB

"Langfuse enables us to track every prompt, response, cost, and latency in real time, turning black-box models into auditable, optimizable assets."

Walid Mehanna

Chief Data & AI Officer at Merck

"Building on Langfuse we saved 30% of external BPO cost by deflecting 50% of support conversations to AI."

Ana Casado

Head of Operations Data and AI at SumUp

"You can connect Claude Code to your Langfuse MCP - or the CLI directly - and it starts fixing and trying until it is fixed."

Paolo Tamagnini

Senior Data Scientist at Trade Republic

"In just a few minutes you're up and running, and you're already able to see what's going on."

Niels Rogge

Machine Learning Engineer at Hugging Face

"Langfuse has made it a lot easier for us at Cresta to iterate on LLM behavior. It has sped up how quickly we can test, learn, improve the model, and build great AI agents."

Jove Zhong

Head of FDE at Cresta

"Building a product like ours would be impossible without Langfuse."

Taylor Halliday

Co-founder at Ravenna

"Having this data set, having this whole test suite that a developer can run on their machine and quickly get results, it's a game changer for us."

Charley David

Principal Engineer at Slite

"I always say it's like the CMS of prompts. It's a game changer."

Martín Siniawski

CEO at Evolve

"When a customer pings us, we instantly open Langfuse. This allows keeping support resolution under 8 minutes."

Alexander Danilowicz

Co-founder at Magic Patterns

"We wanted something built for agents as users first. And that means API first. An agent should never get stuck waiting for a human because of a deficiency in the API. This is what Langfuse is."

David Traina

Data Platform at Ramp

"Langfuse hits the sweet spot between engineering requirements and empowerment of non-technical users to contribute their domain expertise."

Andreas Schuster

Head of Product, AI Help Experience at Canva

"Langfuse has enabled our developers to get extremely fast feedback. It's fundamental to how our developers understand their AI implementations."

Walt Wells

Staff Software Engineer at Khan Academy

"The whole pipeline to improve our chat agent happens entirely in Langfuse. Engineers and domain experts work hand-in-hand."

Laurenz Hemmen

Machine Learning Scientist at DKB

"Langfuse enables us to track every prompt, response, cost, and latency in real time, turning black-box models into auditable, optimizable assets."

Walid Mehanna

Chief Data & AI Officer at Merck

"Building on Langfuse we saved 30% of external BPO cost by deflecting 50% of support conversations to AI."

Ana Casado

Head of Operations Data and AI at SumUp

"You can connect Claude Code to your Langfuse MCP - or the CLI directly - and it starts fixing and trying until it is fixed."

Paolo Tamagnini

Senior Data Scientist at Trade Republic

"In just a few minutes you're up and running, and you're already able to see what's going on."

Niels Rogge

Machine Learning Engineer at Hugging Face

"Langfuse has made it a lot easier for us at Cresta to iterate on LLM behavior. It has sped up how quickly we can test, learn, improve the model, and build great AI agents."

Jove Zhong

Head of FDE at Cresta

"Building a product like ours would be impossible without Langfuse."

Taylor Halliday

Co-founder at Ravenna

"Having this data set, having this whole test suite that a developer can run on their machine and quickly get results, it's a game changer for us."

Charley David

Principal Engineer at Slite

"I always say it's like the CMS of prompts. It's a game changer."

Martín Siniawski

CEO at Evolve

"When a customer pings us, we instantly open Langfuse. This allows keeping support resolution under 8 minutes."

Alexander Danilowicz

Co-founder at Magic Patterns

"We wanted something built for agents as users first. And that means API first. An agent should never get stuck waiting for a human because of a deficiency in the API. This is what Langfuse is."

David Traina

Data Platform at Ramp

"Langfuse hits the sweet spot between engineering requirements and empowerment of non-technical users to contribute their domain expertise."

Andreas Schuster

Head of Product, AI Help Experience at Canva

"Langfuse has enabled our developers to get extremely fast feedback. It's fundamental to how our developers understand their AI implementations."

Walt Wells

Staff Software Engineer at Khan Academy

"The whole pipeline to improve our chat agent happens entirely in Langfuse. Engineers and domain experts work hand-in-hand."

Laurenz Hemmen

Machine Learning Scientist at DKB

"Langfuse enables us to track every prompt, response, cost, and latency in real time, turning black-box models into auditable, optimizable assets."

Walid Mehanna

Chief Data & AI Officer at Merck

"Building on Langfuse we saved 30% of external BPO cost by deflecting 50% of support conversations to AI."

Ana Casado

Head of Operations Data and AI at SumUp

"You can connect Claude Code to your Langfuse MCP - or the CLI directly - and it starts fixing and trying until it is fixed."

Paolo Tamagnini

Senior Data Scientist at Trade Republic

"In just a few minutes you're up and running, and you're already able to see what's going on."

Niels Rogge

Machine Learning Engineer at Hugging Face

"Langfuse has made it a lot easier for us at Cresta to iterate on LLM behavior. It has sped up how quickly we can test, learn, improve the model, and build great AI agents."

Jove Zhong

Head of FDE at Cresta

"Building a product like ours would be impossible without Langfuse."

Taylor Halliday

Co-founder at Ravenna

"Having this data set, having this whole test suite that a developer can run on their machine and quickly get results, it's a game changer for us."

Charley David

Principal Engineer at Slite

"I always say it's like the CMS of prompts. It's a game changer."

Martín Siniawski

CEO at Evolve

"When a customer pings us, we instantly open Langfuse. This allows keeping support resolution under 8 minutes."

Alexander Danilowicz

Co-founder at Magic Patterns

How Langfuse compares

Head-to-head comparisons on features, self-hosting, and pricing.

Langfuse vs. LangSmith

Langfuse vs. Braintrust

Langfuse vs. Arize AX / Phoenix

Langfuse vs. MLflow

Langfuse vs. Pydantic Logfire

All comparisons

Open-source projects using Langfuse

The 25 most-starred open-source projects that depend on the Langfuse Python or JS SDK. See the full list.

Repository	Stars
Significant-Gravitas / AutoGPT	187903
langgenius / dify	160407
langflow-ai / langflow	156333
bytedance / deer-flow	84985
cheaper-inference / OmniRoute	84532
lobehub / lobehub	83873
abi / screenshot-to-code	81022
microsoft / ai-agents-for-beginners	78925
openai / openai-cookbook	76955
cline / cline	71312
BerriAI / litellm	62709
run-llama / llama_index	52806
LibreChat-AI / LibreChat	46745
volcengine / OpenViking	41535
HKUDS / LightRAG	40529
directus / directus	38820
DayuanJiang / next-ai-draw-io	36683
onyx-dot-app / onyx	33212
labring / FastGPT	29994
mastra-ai / mastra	29335
vercel / ai	27740
onlook-dev / onlook	27117
promptfoo / promptfoo	26836
kortix-ai / CompanyOS	20378
gastownhall / gastown	18691