FRENES

LLMOps and observability

MLflow: review, pricing, data and alternatives

MLflow helps teams developing models and LLM applications compare experiment results. It records and versions models, tracks agent and application calls, evaluates responses and supports model deployment. A free tier exists. Access and transparency score: 78/100, #6 of 18 in its category.

Free tierOpen sourceAPILocal processing

What is MLflow?

MLflow helps teams developing models and LLM applications compare experiment results. It records and versions models, tracks agent and application calls, evaluates responses and supports model deployment.

According to its documentation, MLflow lets you:

  • compare experiment results
  • record and version models
  • track calls from agents and LLM applications
  • evaluate generated responses
  • deploy models

We file it under LLMOps and observability, the category of tools to evaluate, monitor and debug AI apps, and it also overlaps with data science and machine learning. The category lists 18 verified tools on this site.

The publisher is Linux Foundation. The service launched in 2018, which gives it some track record.

Who is it for?

It is mostly useful to these profiles: developers, data analysts, and researchers. The need it covers is simple to state: evaluate, monitor and debug AI apps.

MLflow is a good candidate if:

  • you want to try before paying
  • you plan to connect it to your tools or automations through its API
  • you must keep your data in Europe or on your own machine
  • you want to read the code or host it yourself

Before deciding, run a trial on a real task and measure the time saved: it is the only criterion that really counts.

How much does MLflow cost?

Pricing model: open source (public code). Basic use costs nothing.

To estimate what the same work would cost done directly with an AI model, use our API price calculator. Prices change often: always check the official site before subscribing.

Data and privacy

According to its privacy policy, data is processed on your device (local processing).

Local processing is the most favourable case: your files do not leave your machine for the features concerned.

Exporting your content: yes (details on the official site). Being able to get your data back makes switching tools easier later.

Three habits apply to every AI tool:

  • turn off the use of your content for training if the option exists
  • use a work account separate from your personal account
  • review everything the tool produces before publishing or sending it

Platforms, languages and API

MLflow runs on: web browser and API.

Interface languages: English.

A public API lets you call it from your own programs or an automation tool, and plug it into an AI agent.

The source code is public: mlflowmlflow/mlflow.

How we scored it

Our 78/100 score does not judge output quality: it measures what can be publicly verified about access to the tool, its openness and how far the publisher can be trusted.

MLflow score breakdown
CriterionPointsWhat counts
Access15/30free tier, published price, French interface
Openness30/30API, data export, open code
Trust33/40identified publisher, declared hosting, age, presence in reference lists
LangfuseLangfuse : 9595LangSmithLangSmith : 8585OpikOpik : 8383Arize PhoenixArize Phoenix : 8181OvermindOvermind : 7878MLflowMLflow : 7878RespanRespan : 7171Prisma AIRS AI Gateway — PortkeyPrisma AIRS AI Gateway — Portkey : 7171LunaryLunary : 6868TruLensTruLens : 6868
MLflow ranks #6 of 18. The category's top ten are shown.

The full calculation is explained on our method page.

Comparison with alternatives

MLflow against other tools in the lLMOps and observability category:

Comparison within the category
ToolFreeEntry priceAPIScore
MLflowYesnot publishedYes78
LangfuseYes$29 per monthYes95
LangSmithYes$39 per monthYes85
OpikYes$19 per monthYes83
Arize PhoenixYesnot publishedYes81
OvermindYes$120 per monthYes78
RespanYes$199 per monthYes71
Prisma AIRS AI Gateway — PortkeyYes$49 per monthYes71

Verdict

MLflow is a decent option; compare its price and terms with the category leaders.

Strengths

  • Free tier to try it
  • Public API
  • Public source code
  • Local processing available
  • Established since 2018

Frequently asked questions

Is MLflow free?

Yes, a free plan exists, with usage limits.

Where is MLflow data stored?

According to the publisher, on your device (local processing).

Does MLflow have an API?

Yes, a public API is documented.

What are the alternatives to MLflow?

In the same category: Langfuse, LangSmith, Opik, and Arize Phoenix.

MLflow or Langfuse: which one to choose?

Our score is 78/100 for MLflow and 95/100 for Langfuse. Try both on the same task before paying.

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Neutrality. No affiliate links. No vendor pays to be reviewed, rated or ranked. Reviews are directed by François Chollet, neutral and factual, and every data point is dated and sourced. How we score