Skip to content
SPECIFICTION
Get listed

Fluentd

fluentd.org

Free plan WindowsmacOSLinuxSelf-hosted
Visit fluentd.org
Spec score 8.5 #26 of 111 in Log Management Software

What it is

Fluentd is a free, open-source data collector for creating a unified logging layer. It uses JSON to handle log collection, filtering, buffering, and output across sources and destinations. More than 500 community plugins connect it to data sources and outputs, including Elasticsearch and Kibana, Splunk, AWS S3, Kafka, BigQuery, Datadog, and OpenTelemetry. It supports memory and file buffering, failover, and high availability to help prevent data loss between nodes. The project reports that a vanilla instance uses 30–40 MB of memory and can process 13,000 events per second per core. Fluentd v1 runs on Linux, Mac OSX, and Windows; community distributions also include Docker images, a Kubernetes DaemonSet, and Ruby gems. It is self-hosted, and its components are available under the Apache 2 License. The project lists community help and commercial support from companies offering enterprise services. The homepage notes vulnerabilities patched in Fluentd v1.19.3 and advises updating fluent-package to v6.0.4.

Spec sheet

Purpose
Fluentd is an open source data collector for a unified logging layer.Read 11 Oct 2026 · fluentd.org
Deployment options
self-hostedRead 20 Sep 2026 · fluentd.org
Integrations
Listed outputs include Elasticsearch and Kibana, Splunk, AWS S3, Kafka, BigQuery, Datadog, and OpenTelemetry.Read 11 Oct 2026 · fluentd.org
Security
The Fluentd homepage says vulnerabilities CVE-2026-44024, CVE-2026-44025, CVE-2026-44160, and CVE-2026-44161 were patched in Fluentd v1.19.3 and advises updating fluent-package to v6.0.4.Read 11 Oct 2026 · fluentd.org
Support
The project lists community help and commercial support from companies offering Fluentd enterprise services.Read 11 Oct 2026 · fluentd.org
Founded
2011Read 28 Sep 2026 · fluentd.org
Archive export
YesRead 20 Sep 2026 · fluentd.org
Audience and scale
The project says 5,000+ data-driven companies rely on Fluentd and its largest user collects logs from 50,000+ servers.Read 11 Oct 2026 · fluentd.org
Data processing
Fluentd uses JSON to unify log collection, filtering, buffering, and output across sources and destinations.Read 11 Oct 2026 · fluentd.org
History
Fluentd was conceived in 2011 and open-sourced in October 2011.Read 11 Oct 2026 · fluentd.org
License and governance
Fluentd is a CNCF graduated project and its components are available under the Apache 2 License.Read 11 Oct 2026 · fluentd.org
Live log tailing
YesRead 20 Sep 2026 · fluentd.org
Log pipelines
YesRead 20 Sep 2026 · fluentd.org
Plugins
Fluentd has 500+ community plugins connecting dozens of data sources and outputs.Read 11 Oct 2026 · fluentd.org
Reliability
Fluentd supports memory and file buffering, failover, and high availability to help prevent inter-node data loss.Read 11 Oct 2026 · fluentd.org
Resource use
A vanilla Fluentd instance runs on 30–40 MB of memory and can process 13,000 events per second per core.Read 11 Oct 2026 · fluentd.org
Structured log parsing
YesRead 20 Sep 2026 · fluentd.org
Supported systems
Fluentd v1 is available for Linux, Mac OSX, and Windows; community distributions also include Docker images, Kubernetes DaemonSet, and Ruby gems.Read 11 Oct 2026 · fluentd.org

Plans and prices

Fluentd Free Open source data collector · Apache 2 License Read 11 Oct 2026 · fluentd.org

Every Fluentd plan and price →

Strong points and limits

Strong points

  • More than 500 community plugins are available.
  • Supports memory and file buffering.
  • Available for Linux, Mac OSX, and Windows.
  • Open source under the Apache 2 License.
  • Community and commercial support are listed.

Limits

  • Self-hosted deployment is required.
  • The homepage advises updating fluent-package to v6.0.4.
  • Several vulnerabilities are noted as patched in v1.19.3.

Who it suits

Fluentd suits teams building self-hosted log pipelines across varied sources and destinations. Its plugin ecosystem, buffering options, and listed operating-system support fit deployments that need to collect and route structured logs.

Verdict

Fluentd provides a free, self-hosted logging collector with broad plugin support and buffering options. Its project notes identify patched vulnerabilities and recommend a specific fluent-package update, so deployments should account for that guidance.

Where Specifiction places it

Alternatives to FluentdAll alternatives →