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iperf3

Network performance testing tool.

  • Network Services
  • Tools & Utilities
Network performance testing tool. Spawns an iperf3 instance with the settings you put in the "Post Arguments" field (switch to Advanced View to see it). By default that will be a server on port 5201, which can be remapped below. Clearing Post Arguments will show the help text in the log and stop.

Platform availability

Available on 2 of 9 platforms

  • Unraid
  • TrueNAS (not listed)
  • Umbrel (not listed)
  • ZimaOS (not listed)
  • Proxmox
  • Helm (not listed)
  • Mac (not listed)
  • Windows (not listed)
  • Linux (not listed)

Health score?A 0-100 score computed nightly from four factors: maintained (40%: recent commits and steady activity), popular (25%: GitHub stars, log scale), easy to install (20%: platforms, install notes, setup guides, Docker image) and light to run (15%: minimum RAM, ARM support). When the source code has been checked, a fifth factor, security check (20%: automated scan for committed secrets, unsafe desktop-app settings, known-vulnerable dependencies and project hygiene; any serious finding caps it at 20), is added. Factors without data are left out and the rest are rescaled.

73/100 Good

Maintained
95last commit 13 days ago
Popular
798,800 GitHub stars
Easy to install
201 install platform, Docker image
Light to run
No data

Based on 3 of 4 factors.

Availability: platform listings confirmed today, links checked 16 days ago

GitHub stars
8,800
Open issues
244
Last commit
2026-10-02
Latest release
3.22
Activity
rising

Checked 8 days ago - source: GitHub (esnet/iperf)

Resources & Compatibility

ARM (e.g. Raspberry Pi) is supported.

Checked 17 days ago - source: Docker Hub image tags and published docs

First-install notes

No first-install notes yet.

Alternatives (5)

  • DoHSpeedTest - An intuitive web tool for real-time testing of DNS over HTTPS (DoH) server speeds directly in your browser, designed to enhance and optimiz…
  • SmokePing - Smokeping is an open-source network latency and availability monitor that pings a configured list of hosts to continuously graph response t…
  • Speedtest by Ookla - Measures download, upload, and ping speeds; offers global server testing, real-time connection graphs, VPN options, carrier coverage maps,…
  • Tessabyte - An advanced network throughput testing utility for LAN, WLAN, and WAN: TCP/UDP, QoS, custom payloads, reporting, and scheduling.
  • mtr - mtr combines the functionality of the 'traceroute' and 'ping' programs in a single network diagnostic tool.

Checked 14 days ago - source: AlternativeTo

Common questions

Can the iperf3 server handle more than one client at the same time?

No, an iperf3 server accepts a single client simultaneously. You can create multiple parallel streams in one test with the -P option.

How can I reduce CPU usage during a bandwidth test?

Use the -Z or --zerocopy option to send data with sendfile(), which uses much less CPU. On Linux and FreeBSD you can also set CPU affinity with -A.

Can I get machine-readable results from iperf3?

Yes, use the -J or --json option to output the results in JSON format.

Can I run the test in reverse so the server sends data?

Yes, use the -R or --reverse test mode so the server sends and the client receives.

Can I bind the iperf3 server to a specific network interface?

Yes, use the -B option to bind to specific interfaces.

Why might iperf3 results differ between Windows and Linux?

The results can differ because of different parameters and adapter or test-rig setup. Aligning those settings can help make the measurements comparable.

Answers sourced from iperf.fr, www.reddit.com

Community

Collected 16 days ago - public community threads