Input
0x12
Decode
SYN + ACK (handshake step 2)
Developer Tools
TCP Flags Decoder — Interactive Flag Meanings
Enter a hex or decimal TCP flags value to inspect CWR, ECE, URG, ACK, PSH, RST, SYN, and FIN states and meanings interactively.
TCPNetworkProtocol
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开发工具
TCP Flags Decoder
二进制位视图
标志位含义
常见场景
-
Use cases
- Assist packet capture analysis
- Learn TCP flags
- Understand handshake and teardown
How to use
- Enter a flag value or click flags
- Read each flag meaning
- Compare common combinations
Example input and output
FAQ
What does 0x12 mean?
0x12 = SYN + ACK, usually the server response in the TCP three-way handshake.
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