Decompiler.com is a dedicated online service for lifting compiled binaries back into source code.
A free, incredibly powerful software reverse engineering suite created by the National Security Agency (NSA). It includes a highly sophisticated native C/C++ decompiler. exe decompiler online free link
What or framework was used to build the EXE? Decompiler
If you want to quickly inspect a file using a web tool, follow these steps: exe decompiler online free link
This tool "unpacks" the EXE to retrieve the original .pyc files.