Compare software

ngrep vs tcpflow: catalog facts
ngrep	tcpflow
Free Free open-source software.	Free Free and open source.
Windows, Linux, Command line	Linux, Command line
Grep-style matching on packet payloads Accepts tcpdump-style BPF filters	Reconstructs full TCP streams into files Works on live capture or saved pcap files
Text output only, with no protocol decoding like Wireshark Capturing traffic usually needs root or administrator rights	Command-line only Usually built from source
Downloadable app	Downloadable app
Open source	Open source
License not stated	License not stated
No account needed	No account needed
Works offline	Works offline
Official website Full listing and sources Checked September 23, 2026	Official website Full listing and sources Checked October 1, 2026

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