Compare software

nuttcp vs Flowgrind: catalog facts
nuttcp	Flowgrind
Free Free and open source.	Free Free and open source under GPL-3.0-or-later.
Windows, macOS, Linux, Command line	macOS, Linux, Command line
Handles high-throughput TCP and UDP testing beyond typical consumer speed tests Cross-platform command-line tool suited to scripting and automation	Measures several TCP performance metrics Supports distributed tests between arbitrary endpoints
Requires installing and running the tool on both ends of the connection Command-line only, with a learning curve for new users	Supports Linux, FreeBSD and Mac OS X only Requires libxmlrpc-c
Downloadable app	Downloadable app
Open source	Open source
License not stated	License: GPL-3.0-or-later
Not stated if an account is needed	Not stated if an account is needed
Not stated if it works offline	Not stated if it works offline
Official website Full listing and sources Checked September 22, 2026	Official website Full listing and sources Checked October 8, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.