Skip to content
SPECIFICTION
Get listed

FLAML

microsoft.github.io

WindowsmacOSLinuxAPISelf-hosted

What it is

FLAML is free, MIT-licensed open-source software for automated machine learning and tuning. It seeks accurate models or configurations while using low computational resources, and can adapt large language models to applications to reduce monetary costs. Supported AutoML tasks include classification, regression, time-series and panel forecasting, learning to rank, and sequence classification. The flaml.default package recommends data-dependent hyperparameter defaults without runtime tuning. Tuning handles large search spaces, different evaluation costs, constraints, guidance, and early stopping; users can restrict learners or tune a customized learner. Optional integrations include OpenAI models, CatBoost, Vowpal Wabbit, Prophet, statsmodels, Hugging Face Transformers, Ray, Spark, NNI, BlendSearch, Azure Synapse, MLflow, and Azure Machine Learning. Python support for the latest version is 3.10 or later and earlier than 3.14. Ray and Spark enable parallel tuning, but not together, and Spark parallel training does not support GPUs. A .NET implementation is available through ML.NET.

Spec sheet

Purpose
FLAML automates machine learning model selection and hyperparameter tuning with low computational resources.Read 2 Oct 2026 · microsoft.github.io
Integrations
The documentation describes MLflow logging and integration with Azure Machine Learning.Read 2 Oct 2026 · microsoft.github.io
Support
The official site links to a Discord community.Read 2 Oct 2026 · microsoft.github.io
License
The repository is distributed under the MIT License, permitting users to use, copy, modify, publish, distribute, sublicense, and sell the software subject to its conditions.Read 1 Oct 2026 · github.com
.NET support
FLAML has a .NET implementation in the cross-platform ML.NET framework, including Model Builder, the ML.NET CLI, and Microsoft.ML.AutoML.Read 1 Oct 2026 · microsoft.github.io
Auto-tuning
Its tuning approach handles large search spaces, heterogeneous evaluation costs, complex constraints, guidance, and early stopping.Read 1 Oct 2026 · microsoft.github.io
Availability
The repository identifies FLAML as MIT-licensed open-source software.Read 2 Oct 2026 · github.com
Community support
The project provides community support through Discord, issues, discussions, and contributions.Read 1 Oct 2026 · microsoft.github.io
Customization
Users can restrict the learners FLAML tries or tune a customized learner.Read 2 Oct 2026 · github.com
Distributed integrations
FLAML provides optional Ray and Spark distributed tuning, plus NNI, BlendSearch, and Azure Synapse options.Read 1 Oct 2026 · microsoft.github.io
Installation
The Python library can be installed with pip or conda, and optional packages enable features such as AutoML, Hugging Face Transformers, Ray, and Spark.Read 2 Oct 2026 · microsoft.github.io
LLM adaptation
FLAML automatically adapts large language models to applications to reduce monetary costs.Read 1 Oct 2026 · microsoft.github.io
Microsoft Fabric
The repository says FLAML supports AutoML and hyperparameter tuning in Microsoft Fabric Data Science.Read 2 Oct 2026 · github.com
Model integrations
Optional installations include OpenAI models, CatBoost, Vowpal Wabbit, Prophet, statsmodels, and Hugging Face Transformers.Read 1 Oct 2026 · microsoft.github.io
Parallel tuning
FLAML supports Ray and Spark backends for parallel tuning, but a tuning job cannot use both.Read 2 Oct 2026 · microsoft.github.io
Python requirement
The installation documentation requires Python version 3.10 or newer.Read 1 Oct 2026 · microsoft.github.io
Resource efficiency
It finds accurate models or configurations for common ML/AI tasks with low computational resources.Read 1 Oct 2026 · microsoft.github.io
Runtime requirement
The repository specifies Python 3.10 or later and earlier than 3.14 for its latest version.Read 2 Oct 2026 · github.com
Security reporting
The project directs security vulnerability reports to Microsoft Security Response Center for coordinated disclosure rather than public issues.Read 1 Oct 2026 · github.com
Spark limitation
GPU training is not supported when Spark is used as the parallel backend.Read 1 Oct 2026 · microsoft.github.io
Supported tasks
Task-oriented AutoML supports classification, regression, time-series forecasting, panel forecasting, learning to rank, and sequence classification.Read 1 Oct 2026 · microsoft.github.io
Tasks
The documentation lists classification, regression, forecasting, and ranking among the supported AutoML tasks.Read 2 Oct 2026 · microsoft.github.io
Tuning
Its tuning tool handles large search spaces with varied evaluation costs, constraints, guidance, and early stopping.Read 2 Oct 2026 · microsoft.github.io
Zero-shot AutoML
The flaml.default package recommends data-dependent hyperparameter defaults without runtime tuning.Read 1 Oct 2026 · microsoft.github.io

Strong points and limits

Strong points

  • Free MIT-licensed open-source library
  • Supports forecasting, ranking, and sequence classification
  • Handles constraints and early stopping
  • Optional Ray and Spark parallel tuning
  • Python and .NET implementations

Limits

  • Latest version requires Python below 3.14
  • Ray and Spark cannot be combined
  • Spark backend does not support GPU training
  • Optional integrations require additional installation

Who it suits

FLAML suits developers and data scientists building AutoML, forecasting, ranking, or model-tuning workflows. It is useful where low resource use, customization, and optional distributed backends matter.

Verdict

FLAML offers broad AutoML and tuning workflows without a license fee, including forecasting and language-model adaptation. Check Python version requirements and backend limitations before selecting distributed or GPU-based setups.

Where Specifiction places it

Alternatives to FLAMLAll alternatives →