Graylog

Graylog is an AI-powered SIEM and log management platform built for both security and IT operations teams, centralizing and analyzing structured and unstructured machine data from across complex environments in real time to help teams detect threats faster, investigate more efficiently, and control the data-ingestion costs that plague many enterprise SIEM deployments. The platform’s roots as an open-source project give it an unusually large and engaged user community relative to typical commercial SIEM vendors.

Founded in 2009 by Lennart Koopmann in Hamburg, Germany, and now headquartered in Houston, Texas, Graylog serves more than 60,000 organizations across 180 countries. The company sells Graylog Open (a free, open-source tier), Graylog Operations, and Graylog Security, priced based on log ingestion volume — a tiered model that has helped it build broad adoption before converting free users to paid tiers. GigaOm recognized Graylog as a Leader and Outperformer in its 2025 SIEM Radar Report, an independent industry evaluation.

SIEM and log management is a mature but consolidating category dominated by expensive incumbents like Splunk and Microsoft Sentinel. Graylog’s differentiation is its open-source-to-commercial funnel and cost-conscious pricing model, which has driven genuinely broad global adoption, though its scale and analyst recognition still trail the largest, most entrenched SIEM platforms.