Capture files compressed with gzip can be decompressed on the fly.

Read/write many different capture file formats: tcpdump (libpcap), Pcap NG, Catapult DCT2000, Cisco Secure IDS iplog, Microsoft Network Monitor, Network General Sniffer® (compressed and uncompressed), Sniffer® Pro, and NetXray®, Network Instruments Observer, NetScreen snoop, Novell LANalyzer, RADCOM WAN/LAN Analyzer, Shomiti/Finisar Surveyor, Tektronix K12xx, Visual Networks Visual UpTime, WildPackets EtherPeek/TokenPeek/AiroPeek, and many others.

The most powerful display filters in the industry.

Captured network data can be browsed via a GUI, or via the TTY-mode TShark utility.

Multi-platform: Runs on Windows, Linux, macOS, Solaris, FreeBSD, NetBSD, and many others.

Deep inspection of hundreds of protocols, with more being added all the time.

Its open source license allows talented experts in the networking community to add enhancements. The program has all of the standard features you would expect in a protocol analyzer, and several features not seen in any other product. The app is used by network professionals around the world for analysis, troubleshooting, software and protocol development, and education.

Wireshark was written by networking experts around the world and is an example of the power of the open-source. Wireshark's powerful features make it the tool of choice for network troubleshooting, protocol development, and education worldwide. The name might be new, but the software is the same.

The Ethereal network protocol analyzer has changed its name to Wireshark.

Wireshark free