Research and Development

Viewstate is an ASP.Net viewstate decoder, checker, parser and encoder.

It supports both old and new types of viewstate and the data can be extracted directly from the web.


Viewstate is platform independent and can be downloaded in source code or Windows binary formats. If you are building viewstate from source you will need the GNU C compiler (under Windows you can use MinGW).


Viewstate can be downloaded from the Source Forge project page


A Makefile is provided to provide the usual compilation process of:

  • make
  • make install (as root)

However, you can compile it manually with the following:

gcc -o viewstate viewstate.c


If viewstate is run with no options, the online help is displayed. But a simple decode of the viewstate data held by the Acme company web site would be:

viewstate --decode --url=http://www.acme.fake/main.asp


Viewstate is covered by the GPL v3 license.

Link to project:

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