autocannon vs Apache JMeter

Free and open source

Free and open source

Free and open source. You pay in engineering time and CI minutes.

Free. Costs are load-generator infrastructure and, commonly, a cloud execution service such as BlazeMeter.

Everything, self-hosted

Everything, self-hosted

Established

OSS community · since 2016

Category standard

Apache Software Foundation · since 1998

• Zero configuration; useful output in seconds.
• Good percentile reporting for such a small tool.
• Scriptable from Node for micro-benchmarks in CI.

• Protocol coverage no modern tool matches — JDBC, JMS, LDAP, mainframe-adjacent protocols.
• GUI test-plan building is accessible to testers who do not code.
• Enormous body of documentation, plugins and available expertise.

• Single endpoint only — no user journeys, no correlation, no think time.
• No distributed execution.
• HTTP/1.1 focused.

• Thread-per-user model is memory-hungry; high load needs a cluster where k6 needs one box.
• JMX test plans are XML that merges terribly in version control.
• The GUI must not be used for actual load generation, which trips up nearly every beginner.

Quick endpoint benchmarks and micro-optimisation work.

Enterprise performance teams needing protocol breadth and a GUI-based workflow.