# tshark > Packet analysis tool, CLI version of Wireshark. > More information: . - Monitor everything on localhost: `tshark` - Only capture packets matching a specific capture filter: `tshark -f '{{udp port 53}}'` - Only show packets matching a specific output filter: `tshark -Y '{{http.request.method == "GET"}}'` - Decode a TCP port using a specific protocol (e.g. HTTP): `tshark -d tcp.port=={{8888}},{{http}}` - Specify the format of captured output: `tshark -T {{json|text|ps|…}}` - Select specific fields to output: `tshark -T {{fields|ek|json|pdml}} -e {{http.request.method}} -e {{ip.src}}` - Write captured packet to a file: `tshark -w {{path/to/file}}` - Analyze packets from a file: `tshark -r {{path/to/file.pcap}}`