We have found 4 software records in our database eligible for .stp to .sldprt file format conversion.
If you have access to SolidWorks you can simply import STEP product data (.stp, .step) to the program and save the data as one of the part files (.prt, .sldprt).
Without SolidWorks, you have to use some of the other alternative CAD software with SolidWorks format support, or some kind of dedicated CAD conversion solutions.
A popular is 2D and 3D CAD (computer-aided design) and CAE (computer-aided engineering) construction software for Microsoft Windows developed by SolidWorks Corporation.
A dedicated CAD converter with a large file format support that allows users to convert (translate) CAD designs or drawings between different formats. CrossManager is a commercial product, you will need to purchase a license. It is available in English, French, German, Italian, Czech, Chinese, Russian and Korean language.