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AI · alternatives · 2026

24 alternatives to Langfuse

Open source tracing and analytics for LLM applications

Langfuse is an open-source observability platform for developers building LLM applications. It provides visual tracing and logging tools to explore and debug complex application behavior, along with analytics… Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. Langfuse launched in 2023; newer entries below may have overtaken it.

  1. 1

    Hi HN! Langfuse is OSS observability and analytics for LLM applications (repo: https://github.com/langfuse/langfuse, 2 min demo: https://langfuse.com/video, try it yourself: https://langfuse.com/demo) Langfuse makes capturing and viewing LLM calls (execution traces) a breeze. On top of this data, you can analyze the quality, cost and latency of LLM apps. When GPT-4 dropped, we started building LLM apps – a lot of them! [1, 2] But they all suffered from the same issue: it’s hard to assure quality in 100% of cases and even to have a clear view…

    2023 · github.com · its alternatives →

  2. 2

    Improve your LLM apps with open-source observability tool

    2024 · langtrace.ai · its alternatives →

  3. 3

    Open-source LLM Observability for Developers

    2024 · helicone.ai · its alternatives →

  4. 4

    The low-code platform for testing AI apps

    2024 · langtail.com · its alternatives →

  5. 5
    LangWatch▲669

    Founder here. Langy is an AI engineer that lives inside our platform, LangWatch. It reads your production traces, writes Scenario tests and evaluations for the problems it finds, opens a pull request on your repo, and proves the fix by running those simulations in CI. A human still merges. Reachy robot from Hugging Face arrived on the same week we were planing on launching it, so we wanted to use for the launch. So we it wired to our Langy which actually lives on the platform, and asked it to test our own customer-support voice agent. On the video you can see it writing the agent tests…

    2024 · langwatch.ai · its alternatives →

  6. 6

    OpenTelemetry-native observability for agents and LLMs

    Aug 2026 · openobserve.ai · its alternatives →

  7. 7
    Openlit▲152

    One click observability & evals for LLMs & GPUs

    2024 · openlit.io · its alternatives →

  8. 8

    If you've built any web-based app in the last 15 years, you probably used something like Datadog, New Relic, Sentry, etc. to monitor and trace your app, right? Why should it be different when the app you're building happens to be using LLMs? So today we're open-sourcing OpenLLMetry-JS. It's an open protocol and SDK, based on OpenTelemetry, that provides traces and metrics for LLM JS/TS applications and can be connected to any of the 15+ tools that already support OpenTelemetry. Here's the repo: https://github.com/traceloop/openllmetry-js A few months ago we launched…

    2024 · github.com · its alternatives →

  9. 9
    traceAI▲273

    Open-source LLM tracing that speaks GenAI, not HTTP.

    Apr 2026 · github.com · its alternatives →

  10. 10

    Hey HN, Nir, Gal and Tomer here. We’re open-sourcing a set of extensions we’ve built on top of OpenTelemetry that provide visibility into LLM applications - whether it be prompts, vector DBs and more. Here’s the repo: https://github.com/traceloop/openllmetry. There’s already a decent number of tools for LLM observability, some open-source and some not. But what we found was missing for all of them is that they were closed-protocol by design, vendor-locking you to use their observability platform or their proprietary framework for running your LLMs. It’s still early in the…

    2023 · github.com · its alternatives →

  11. 11LO

    Hey HN, Ola and Karthik here. We are working on Langtrace(https://github.com/Scale3-Labs/langtrace), an open source, open telemetry based SDK and monitoring/evaluations client for LLM based applications. The SDK generates OTEL standard spans and traces for popular LLMs like OpenAI, Anthropic and Cohere, popular frameworks like Langchain and LlamaIndex and vectorDBs like ChromaDB and Pinecone. The LLM monitoring/evaluations space has seen a number of products off late, both open source and closed source ones. But, a couple of things we have observed are: lack of…

    2024 · its alternatives →

  12. 12
    LLMonitor▲128

    Open source monitoring and production toolkit for AI apps

    2023 · its alternatives →

  13. 13

    Langtrace 🔍 is an open-source, Open Telemetry based end-to-end observability tool for LLM applications, providing real-time tracing, evaluations and metrics for popular LLMs, LLM frameworks, vectorDBs and more.. Integrate using Typescript, Python. 🚀💻📊 - Scale3-Labs/langtrace

    2024 · github.com · its alternatives →

  14. 14

    Fix bugs faster with open source, AI native observability

    2025 · traceroot.ai · its alternatives →

  15. 15

    Ship AI apps with fewer surprises

    2024 · langtail.com · its alternatives →

  16. 16

    See what your Claude Code sessions actually cost

    Jul 2026 · langwatch.ai · its alternatives →

  17. 17
    LangSmith▲350

    Build and deploy LLM applications with confidence

    2023 · langchain.com · its alternatives →

  18. 18

    Hey HN, we're super excited to share something we've been working on: OpenLIT. After an engaging preview that some of you might recall, we are now proudly announcing our first stable release! *What's OpenLIT?* Simply put, OpenLIT is an open-source tool designed to make monitoring your Large Language Model (LLM) applications straightforward. It’s built on OpenTelemetry, aiming to reduce the complexities that come with observing the behavior and usage of your LLM stack. *Beyond Basic Text Generation:* OpenLIT isn’t restricted to just text and chatbot outputs. It now includes automatic…

    2024 · github.com · its alternatives →

  19. 19
    Langdock▲294

    Create, deploy, test & monitor ChatGPT plugins in minutes

    2023 · langdock.com · its alternatives →

  20. 20
    TraceLLM▲100

    OpenTelemetry for production AI applications

    Jul 2026 · tracellm.in · its alternatives →

  21. 21

    Hi HN, Hugh and Vince here. LLMonitor helps you record, trace & search your LLM queries and chatbot conversations. You can also capture user feedback on your frontend and correlate it with backend LLM queries then use that to fine-tune your own models. The project started has an internal tool in our previous (failed) AI startup. We’re aware the LLM observability space is very crowded. Apart from being open-source, we differentiate with: - Model-agnostic and minimal lock-in (no MITM of requests). - High focus on DX and dashboard clarity. - Support for complex scenarios: e.g. a chatbot that…

    2023 · github.com · its alternatives →

  22. 22

    LLM application development, monitoring, and testing

    2024 · smith.langchain.com · its alternatives →

  23. 23

    Hey HN, I made Browser-Use, an open-source tool that lets (all Langchain supported) LLMs execute tasks directly in the browser just with function calling. It allows you to build agents that interact with web elements using natural language prompts. We created a layer that simplifies website interaction for LLMs by extracting xPaths and interactive elements like buttons and input fields (and other fancy things). This enables you to design custom web automation and scraping functions without manual inspection through DevTools. Hasn't this been done a lot of times? Good question, as a general…

    2024 · github.com · its alternatives →

  24. 24

    Over the holidays, I started hacking together a CLI to translate my app, Midday. Now, it’s ready for you to use and start translating your app in seconds! I’d love to hear your thoughts!

    2024 · languine.ai · its alternatives →

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Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →

Langfuse alternatives (2026): 24 similar tools