DVD & Blu-ray disc capacity

DVD-5, DVD-9 are the two most common DVD formats.

A DVD-5 is a single-layer DVD that holds up to 4.7GB of data (around 120-133 minutes of standard definition video depending on compression).

A DVD-9 is a dual-layer DVD that holds up to 8.5GB of data (around 240 minutes of video depending on compression). This DVD consists of a solid layer and a semi-transparent layer that allows for almost twice the data of a DVD-5 and is often used to retain a higher bitrate (quality) that may not be feasible on a DVD-5.

Likewise, Blu-ray disc (BD) which is delivered high-definition video content is available in two different formats, BD-25 & BD-50

A BD-25 is a single-layer BD that holds up to 25GB of data (around 120-133 minutes of high definition video depending on compression).

A BD-50 is a dual-layer BD that holds up to 50GB of data (around 240 minutes of high definition video depending on compression).