iperf3 vs Netperf

iperf3 is a free command-line network measurement tool that reports achievable IP-network bandwidth, throughput, loss, and related results. It includes client and server functions for TCP, UDP, and SCTP tests, with adjustable timing, protocol, and buffer settings. Client or server output can be emitted as JSON, including line-delimited JSON for real-time parsing, and a library version can be embedded in other programs. The project uses a three-clause BSD license and lists Ubuntu Linux, FreeBSD, and macOS as its officially supported platforms. Windows is not officially supported; its FAQ points users with Windows problems toward iperf2. ESnet supplies source distributions rather than binary packages and recommends checking SHA256 checksums. iperf3 began as a perfSONAR bandwidth tester, its primary user base. It is not backwards compatible with the original iperf. Version 3.22 was released September 29, 2026.

Netperf is an open-source, self-hosted utility for measuring network performance. It reports unidirectional throughput and end-to-end latency through a client-server arrangement: netperf runs tests and netserver supplies the server side. Netserver can run as an inetd child or standalone daemon. The manual describes TCP and UDP transfer and request/response tests over IPv4 and IPv6 sockets, plus XTI, DLPI, Unix domain socket, and SCTP tests. Where the platform and build support it, results can include CPU utilization and service demand. Optional configuration enables STREAM pacing, timing histograms, and interim results. The primary distribution is source code, intended for systems without readily available binaries. Reported Windows builds use Cygwin, the Windows DDK, or Microsoft Visual Studio 2003; the README discusses an OSX naming workaround. Hewlett Packard Enterprise released this version under the MIT license. The project warns that its manual may be outdated, and several test families require explicit configuration.