VoIP calls are made using codecs. There are several codecs available for telecommunications. A codec compresses and uncompresses audio and video phone call files and determines how much data VoIP uses. The table below shows approximately how much data a 10-minute and 1-hour VoIP call uses with the various codecs. Codec Data (10 Mins) Data (1 Hour) G.711 102 MB 613 MB G.729 36 MB 219 MB G.723.1 24 MB 146 MB G.726 71 MB 426 MB