The best replacement for aspx is html.

The best alternatives to aspx are rated as following:
★★★★★  html
★★★★  asp
★★★★  ascx
★★★  razor
★★★  asmx
★★★  cshtml
★★  ashx
★★  razor view engine
★  razor performance
  htm
  razor engine
  mspx

Your alternative for aspx is not listed? Suggest!
Speaking about aspx, one probably shouldn't forget about mvc.

Other search terms related to aspx and their ratings are:
★★★★★ mvc
You have in mind a companion for aspx and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of aspx in all years. Click on graph for more.
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