Exeinfo PE is a free portable tool which can tell you more about executable and other file types.
This starts with some useful general information. Is it 32, or 64-bit? Windows GUI, or console-oriented?
The signature gives you details on the file type. If it's an executable, you might see whether it's a setup program, a C++ executable, a .NET file, Visual Basic or whatever, along with details of any detected packer. But the program can also identify and tell you more about other file types - images, archives, documents, more - even if they don't have their original extensions.
Exeinfo PE also has a ripper to locate and extract other file types within your target file. This can be helpful for security analysis - finding a hidden executable, say - but you can also use it to extract images, videos and other resources which might be embedded inside a file.
The program also displays information on a file's digital certificate, if any. It offers extra tools to scan for suspect strings (Registry calls), and there's a vast amount of low-level detail for experts (entry points/ corrector, overlay option, section stripper, more).
ver.0.0.4.3 with 960/49 signatures , Base64 exe Ripper added , RSDS Ripper
It's not nearly as polished as pestudio, but Exeinfo PE can still provide useful information about suspect or mystery files.