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Best Anomaly Detection Software in 2026

Anomaly detection software helps surface patterns that fall outside expected behavior in the data you monitor. Compared on detection method, real-time detection, anomaly explanations, and supported data, these entries also differ in data retention and deployment options. Free-plan availability and paid-from pricing give you further details to weigh. ManageEngine NetFlow Analyzer, OpenSearch, and PyOD are among the named options. Consider what data you need to watch, whether you need explanations alongside alerts, and how each product’s stated detection and deployment details fit your requirements.

  1. 1

    Anomalib

    Free plan Open source APILinuxSelf-hosted+2

    Anomalib combines model development and benchmarking with several inference and deployment routes.

    9.3 Open source Visit site
  2. 2

    Axomaly

    Free plan APIWeb

    Axomaly offers API-based anomaly detection with details that can be used in existing workflows. Its free alpha is limited to one metric, and detection depends on sufficient metric history.

    7.3 Visit site
  3. 3

    OpenSearch

    by OpenSearch
    Free plan APILinuxMac+3

    OpenSearch provides a free search and analytics suite with ingestion, visualization, and machine-learning capabilities.

    7.2 Open source Visit site
  4. 4

    ObservabilityOS

    Free plan APISelf-hostedWeb

    ObservabilityOS combines telemetry collection, anomaly detection, and incident follow-up in one platform.

    7.1 Free plan · paid from $29/mo Visit site
  5. 5

    PyOD

    Free plan APILinuxMac+2

    PyOD offers a broad detector catalog with both a classic API and an orchestration layer.

    7.1 Free plan Visit site
  6. 6

    Metaplane

    Free plan APIWeb

    Metaplane covers a broad set of data checks and connects with listed warehouse, BI, and alerting tools. Review plan limits closely if you need more tables, lineage, or Data CI/CD.

    7.0 Free plan · 14-day trial Visit site
  7. 7

    PySAD

    Free plan LinuxMacWindows

    PySAD brings online detectors and workflow utilities together for streaming anomaly detection.

    6.9 Free plan Visit site
  8. 8

    Soda

    Free plan APILinuxSelf-hosted+1

    Soda combines data testing, observability, and contracts for teams managing data quality across workflows.

    6.9 Free plan · paid from $750/mo Visit site
  9. 9

    ManageEngine NetFlow Analyzer

    Free plan AndroidiPhoneLinux+2

    NetFlow Analyzer combines bandwidth monitoring, application visibility, and conversation analysis with support for multiple flow protocols.

    6.8 Free plan · paid from $172 · 30-day trial Visit site
  10. 10

    OpenUBA

    Free plan APISelf-hostedWeb

    Choose OpenUBA if you want a free, open-source framework for behavior analytics, with configurable models, alert rules, and case workflows.

    6.8 Open source Visit site
  11. 11

    ExtraHop RevealX

    Free trial APILinuxSelf-hosted+1

    Choose RevealX if your enterprise needs unified network detection, performance visibility, and packet forensics across hybrid environments.

    6.3 Pricing on request Visit site
  12. 12

    Progress Flowmon

    Free trial APILinuxSelf-hosted+1

    Choose Progress Flowmon if you need network visibility and behavior-based security monitoring in one platform, with deployment options spanning virtual, cloud, and hardware appliances.

    6.1 Pricing on request · 30-day trial Visit site
  13. 13

    Cisco Catalyst Center

    Paid APILinuxMac+3
    5.9 Pricing on request Visit site
  14. 14

    Corelight Open NDR

    Paid APILinuxSelf-hosted+1

    Corelight Open NDR combines detection, traffic analysis, and response workflows across several deployment types.

    5.9 Pricing on request Visit site
  15. 15

    Darktrace / EMAIL

    Paid APIWeb

    Darktrace / EMAIL combines behavioral threat detection with response options and coverage beyond inbound email. Pricing requires a request, while a 30-day trial is listed.

    5.5 Pricing on request · 30-day trial Visit site
  16. 16

    Vectra AI Identity Threat Detection and Response

    Free trial APIWeb

    Choose Vectra ITDR if your security team needs to monitor identity activity across network and cloud environments and wants investigation and response capabilities.

    5.5 Pricing on request Visit site
  17. 17

    rrcf

    Free plan
    5.3 Free plan Visit site
  18. 18

    Securonix UEBA

    Paid Web

    Securonix UEBA combines behavioral baselines, peer analysis, prebuilt use cases, and threat models for security investigations.

    4.9 Pricing on request Visit site
  19. 19

    Anodot

    Paid Web
    4.8 Pricing on request Visit site
  20. 20

    Anomalo

    Paid Web

    Choose Anomalo if you need machine-learning anomaly detection across several data formats and value anomaly explanations or hybrid deployment.

    4.6 Pricing on request · 30-day trial Visit site
  21. 21

    Cisco Meraki Dashboard

    Paid Web
    4.4 Pricing on request Visit site
  22. 22

    Quest Data Quality

    Paid Web
    4.0 Pricing on request Visit site

#1Places #1, #2, #3, #4, #5 on this list can be bought by the makers of the software on it. See the price

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