how to change file format online

http://www.online-convert.com/
www.zamzar.com/
www.mediaconverter.org/
http://www.youconvertit.com/ConvertFiles.aspx   r       www.youconvertit.com/
online.movavi.com/ - United States
www.freemake.com/free_video_converter/
www.moyeamedia.com 
so all i have listed r 4 converting 
but i suggest  http://www.online-convert.com/ cuz thats good
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