UDP Example

Checksum Zero

Examine a UDP packet with checksum set to zero. In IPv4, UDP checksum is optional—setting it to 0x0000 means the sender skipped calculation, useful for performance-critical paths.

Hex Data

05 D0 12 34 00 10 00 00 41 42 43 44 45 46 47 48
Note: In IPv4, UDP checksum is optional, setting to 0x0000 means not calculated
Load in Visualizer
checksumipv4

Field Breakdown

Source Port
Source port number (0-65535)
1488
Destination Port
Destination port number (0-65535)
4660
Length
Length of UDP header and data in bytes (minimum 8)
16
Checksum
Checksum for error detection (optional in IPv4, mandatory in IPv6)
0x0000

Related Resources

UDP Protocol Visualizer - Parse & Analyze UDP PacketsUDP Header Format and Fields Explained - ByteLensSource Port - Definition, Range, and Usage in NetworkingDestination Port - Definition, Range, and Usage in Networking

About UDP

User Datagram Protocol (RFC 768)

Fields: 4
Endianness: big
Specification: RFC 768