Outlier Detection Python Packages

pyod

A Python library for anomaly detection across tabular, time series, graph, text, image, and audio data. 60+ detectors, benchmark-backed ADEngine orchestration, and an agentic workflow for AI agents.

tsmoothie

A python library for time-series smoothing and outlier detection in a vectorized way.

cleanlab

Cleanlab's open-source library is the standard data-centric AI package for data quality and machine learning with messy, real-world data and labels.

minisom

:red_circle: MiniSom is a minimalistic implementation of the Self Organizing Maps

pynomaly

Anomaly detection using LoOP: Local Outlier Probabilities, a local density based outlier detection method providing an outlier score in the range of [0,1].

deadwood

Deadwood: Outlier Detection via Pruning Mutual Reachability Minimum Spanning Trees

handyspark

HandySpark - bringing pandas-like capabilities to Spark dataframes

suod

(MLSys' 21) An Acceleration System for Large-scare Unsupervised Heterogeneous Outlier Detection (Anomaly Detection)

quitefastmst

quitefastmst: Euclidean and Mutual Reachability Minimum Spanning Trees

isotree

(Python, R, C/C++) Isolation Forest and variations such as SCiForest and EIF, with some additions (outlier detection + similarity + NA imputation)

dataeval

Python library for analyzing data quality and its impact on model performance across classification and object-detection tasks.

lumbermark

Lumbermark: Resistant Clustering via Chopping Up Mutual Reachability Minimum Spanning Trees

pythresh

Outlier Detection Thresholding

tsod

Anomaly Detection for time series data

dataeval-plots

Python library for analyzing data quality and its impact on model performance across classification and object-detection tasks.

fastdup

fastdup is a powerful, free tool designed to rapidly generate valuable insights from image and video datasets. It helps enhance the quality of both images and labels, while significantly reducing data operation costs, all with unmatched scalability.

cleanlab-studio

Client interface to Cleanlab Studio

diive

Time series processing library

stormlog

GPU memory profiler for PyTorch, JAX & TensorFlow — real-time monitoring, leak detection, OOM flight recording, distributed analysis, and interactive TUI.

pysad

Streaming anomaly detection in Python: 16 online detectors (xStream, LODA, RS-Hash, Half-Space Trees, RRCF…) plus calibration and prequential evaluation for real-time data.

nonconform

Conformal Anomaly Detection & Change-Point Detection

robustcov

Robust scatter geometry for anomaly detection, kernels, and ML workflows in Python.

numalogic

Collection of operational time series ML models and tools

visualqc

VisualQC : assistive tool to ease the quality control workflow of neuroimaging data.