As I test new sites and services and I am seeing coming new services are better than old ones. There are many online file conversion services but this one I found more useful.
Fileminx is an online file conversion service, it does not support online services like YouTube so you have to upload a document form your computer. It is a free online conversion service for document, image, music and video. It is 100% free and no need to open an account. It supports up to 50 MB file size. It is a real-time file conversion service you do not have to wait , do not have supply email address so just upload something from your computer and convert it and download it. As they said it is safe and virus free.
You do not have to specify a file format it will detect it automatically. For online file conversion it is an all in one solution, if a file is supported for input format that will also be supported for output format.
go to Fileminx