iperf3

Network throughput tester

medium risk

interactive breakdown — edit the command and press Explain
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⚠ Risks & cautions
What it does

Measures bandwidth between a server and a client.

Common flags
FlagMeaning
-sServer mode
-cClient mode
-tDuration
-PParallel streams
-RReverse direction
Examples
iperf3 -sStart the server · explain & risk-check →
iperf3 -c host -t 1010-second test · explain & risk-check →
Related
ping mtr
Open the full explainer →More in Networking

Reference text is hand-written and may be incomplete — check man iperf3 for your version. Test destructive commands on a non-production system first.