Both .obj and .ply files contain 3D models, albeit in a little different format. It may be possible that one can be converted to another and vice versa using some of the dedicated 3D modeling programs or even dedicated conversion programs.
Convert 3D object graphics to Polygon graphics.
We have found 12 software records in our database eligible for .obj to .ply file format conversion.
Microsoft Windows software - convert obj to ply on Windows
A very popular free program used for work with 3D graphics
Convert from obj file format
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned obj to ply. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
A 3D CAD translation softwate
Create models and print in 3D
A professional manufacturing data preparation software
A converter for 3D formats
A dedicated CAD converter
Apple macOS / Mac OS X software - convert obj to ply on OS X
A Mac version of the popular 3D visualisation software
The Mac version of popular free 3D graphics software
Linux/Unix software - convert obj to ply on Linux
Easy-to-use 3D modeling utility
Multiplatform software - convert obj to ply on any platform
A 3D point cloud processing software
An open source system for 3D triangular meshes
On-line services software - convert obj to ply on web
A free online 3D model conversion service