MTU and MSS Calculator

MTU/MSS Tunnel Calculator

Calculate effective MTU and TCP MSS for tunneled traffic

Underlying MTU
Tunnel Type
Tunnel Type
—
Tunnel MTU
—bytes
TCP MSS
—bytes
Overhead: —

How to Use this tool:

To use this tool, you will want to know the underlying connection and its MTU.  We have a few other tools for MTU discovery that you might find useful as well.  One is a script you can run from your computer and the other is an ICMP reflector.  

Once you have your MTU select a tunnel type.  We do have a tunnel section guide as well if you have questions on what service to use. 

With this information correct your tunnel MTU and IPv4 MSS values will be displayed in the window.  With this information be sure to update the MSS settings on your tunnel interface as needed.