Scene files saved in Maya Ascii format (.ma) can be also exported to other 3D formats, including X3D graphics models (.x3d). You can definitely make it using Autodesk Maya, but if you do not have access to this software you need to rely on some dedicated 3D/CAD translation software, such as PolyTrans.
Convert Autodesk Maya ASCII scene to X3D graphics model.
We have found one software suitable in our database for this conversion.
Microsoft Windows software - convert ma to x3d on Windows
A software suite used for 3D CAD/DCC + Animation/Model/NURBS/Skinning translation, optimization and viewing.
Convert from ma file
to x3d file
The table with program actions contains information about what each program is capable of doing with their files. This may be a good pointer for further searches for certain file conversions and help you find the converter you are looking for if our search result is insufficient for you. However, it is far from perfect and may sometimes show results which are not really usable because of the nature of the software handles the files. So a conversion that appears as possible, just because of matched actions, may in fact not be possible.