Upload your WMA file using the picker above and the converter detects the source type and runs the WMA → MP4 pipeline. The result downloads automatically when conversion completes; no account needed for one-off conversions. WMA是Windows Media Audio,微软对MP3的回答,1999年启动,并被包装在那个时代的每个Windows安装上。 MP4是ISO/IEC 14496-14,2001年标准化,源自于同样的快速时装箱布局MOV用途。