iperf3

At a glance

• Editor score
  7.5 / 10
• Pricing
  Free plan
• Best for
  Embedded and Linux/macOS throughput testing
• Free plan
  Yes
• Paid from
  Free
• Path visualization
  No
• Founded
  2010
• Facts checked
  20 Sep 2026

• Where it wins

  • Tests TCP, UDP, and SCTP in client or server mode
  • Reports throughput, bitrate, and packet loss with optional JSON output
  • Supports zero-copy mode, CPU affinity, and the embeddable libiperf library

• Where it doesn't

  • Official platform support is limited to Ubuntu Linux, FreeBSD, and macOS
  • No built-in path visualization or DNS diagnostics
  • ESnet does not distribute binary packages

Our verdict on iperf3

iperf3 is an open-source command-line tool for measuring achievable bandwidth between IP hosts. It suits network engineers, developers, research and education networks, and teams building throughput checks into other programs. Client and server operating modes support TCP, UDP, and SCTP testing, with results covering throughput, bitrate, and packet loss. The project is distributed under a three-clause BSD license and is used by perfSONAR, ESnet, and general networking users.

Pricing is straightforward: iperf3 is free and open source. The main setup consideration is distribution. ESnet does not distribute binary packages; its official documentation lists third-party packages and source distributions instead. That makes iperf3 a practical fit for users comfortable with command-line tools, source distributions, or platform package options. Officially supported platforms are Ubuntu Linux, FreeBSD, and macOS, while Windows, Android, and iOS are not officially supported.

Its strongest area is controlled throughput testing rather than broad network diagnosis. Users can configure timing, protocols, and socket buffers, request JSON output, enable zero-copy transmission, and set CPU affinity. The libiperf library also supports embedding functionality in other programs, while perfSONAR provides an ecosystem connection. Choose iperf3 for focused, scriptable bandwidth and packet-loss measurement, especially when embedding or automation matters. Choose another tool if you need path visualization, DNS diagnostics, or officially supported Windows, Android, or iOS deployments.

Your product? Our editors can test iperf3 in depth and publish a review, labelled as paid · from $99/mo →

iperf3 pricing

iperf3 fact sheet

iperf3 integrations

iperf3 lists 1 integrations on its own site.

• perfSONAR

Alternatives to iperf3

• GlobalpingA broad, open-source toolkit for diagnosing network behavior across global locations.9.4
• RIPE AtlasA free platform for distributed measurements, path analysis, and public Internet reachability data.9.2
• PingPlotterA focused tool for tracking latency, packet loss, jitter, and network paths.9.0

See all iperf3 alternatives →

Featured on iTechGuides

iperf3 is listed in our Network Diagnostic Software directory. Add the badge to your site — it links back to this page.

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Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026

Advertiser disclosure: iTechGuides is reader-supported. Vendors can pay for top positions in our rankings and for a place on other products' pages, and we may earn a commission when you click some links. Bought places stand at the number bought; this page and our disclosure say so. Paying vendors may get a fuller, more detailed review from our editors, and that review can change their score. How we rank.

Last updated 7 Oct 2026 · How we research and update