Network Protocol Utilities

Online packet parsing tools for decoding hex dumps, protocol headers, MAC addresses, IP packets, TCP/UDP segments, DNS messages, and Ethernet frames. ByteLens provides a focused set of free, browser-based network utilities built for students, network engineers, security analysts, and curious developers who need to inspect protocol data quickly without installing software, signing up for an account, or uploading captures to a remote server.

Our Hex to Packet Parser is a versatile hex packet parser that turns raw hexadecimal dumps into structured protocol fields. Paste any UDP, TCP, IPv4, IPv6, DNS, or Ethernet II hex string and the tool instantly maps every byte to its corresponding header field, showing field names, decimal and hexadecimal values, and concise RFC-aligned descriptions. The interactive byte grid highlights the bytes that belong to each field, so you can visually trace how source ports, destination addresses, flags, and checksums are encoded. Whether you are troubleshooting a captured frame, preparing for a networking certification, writing a homework assignment, or teaching packet structure in a classroom, the parser gives you immediate, accurate feedback and supports JSON, CSV, binary, SVG, and PNG export.

For data-link layer analysis, our MAC address tools include the MAC OUI Lookup. Enter a MAC address or OUI prefix in colon, hyphen, Cisco dot, or plain hex format, and the tool returns the registered vendor or manufacturer using an IEEE public registry snapshot. This is invaluable when you are decoding Ethernet frames, verifying device hardware vendors, auditing network inventory, or mapping endpoints on a local network. Combined with our Ethernet II visualizer, the lookup bridges raw MAC addresses to real-world hardware context.

Both utilities are protocol header tools that run entirely in your browser. There is no server-side processing of your payload data, no registration requirement, and no artificial usage limits. You can move between tools, load built-in examples, copy results, and share URLs freely. Start with the Hex to Packet Parser for general packet decoding, or jump directly to MAC OUI Lookup when you need to identify the vendor behind a MAC address.