The best free alternative to tcpdump is Wireshark, which is also Open Source. If that doesn't suit you, our users have ranked more than 25 alternatives to tcpdump and many of them is free so hopefully you can find a suitable replacement. Other interesting free alternatives to tcpdump are NetworkMiner, Sysdig, Termshark and MicroOLAP TCPDUMP.
Wireshark is a premier network protocol analyzer used globally in industries and education, offering multi-platform support, deep protocol inspection, powerful display filters, and VoIP analysis. It allows both live capture and offline analysis, supporting various networks and protocols.
NetworkMiner is a Network Forensic Analysis Tool (NFAT) for Windows. NetworkMiner can extract transmitted files and certificates from PCAP files containing HTTP, FTP, SMB, SMB2, TFTP and several other protocols.
Sysdig is open source, system-level exploration: capture system state and activity from a running Linux instance, then save, filter and analyze. Think of it as strace + tcpdump + lsof + awesome sauce.
MicroOLAP TCPDUMP is a clone of tcpdump , the most used network sniffer/analyzer for UNIX, compiled with the original tcpdump code (http://www.tcpdump.org/), and MicroOLAP Packet Sniffer SDK.
PCAPdroid is an android app to capture the phone traffic and analyze it remotely (e.g. via Wireshark). The traffic can be easily downloaded from a remote device thanks to the integrated HTTP server, or streamed to a remote UDP receiver.
justniffer is a TCP sniffer. It reassembles and reorders packets and displays the tcp flow in a customizable way. It can log network traffic in web server log format. It can also log network services performances and extract http content.
correctly extract the tcp content
Native Cocoa app for capturing and analyzing packets. Similar to Wireshark, but with a native interface (and less features). If you don't like the X11 GTK Wireshark, this is your app.
SmartSniff is a packet sniffer that capture TCP/IP packets and display them as sequence of conversations between clients and servers. You can view the TCP/IP conversations in Ascii mode (for text-based protocols, like HTTP, SMTP, POP3 and FTP) or as hex dump (for non-text base...
HttpCanary is a powerful HTTP/HTTPS/HTTP2/WebSocket/TCP/UDP packets capture and analyzer app designed for Android platform.
United States
Sweden
EU
Ukraine
Italy
Israel
Belgium
good for tracing on remote machine