What Is the Difference Between DVD & Blu-Ray?

By Lou Martin

In 2010, digital video discs (DVDs) and Blu-ray discs are the norm in home entertainment. Blu-ray is a brand name and is the name of the optical disc developed by the Blu-ray Disc Association (BDA), which includes several top consumer electronics companies that have worked jointly to develop the technology. Several key differences have made the Blu-ray disc the official successor to the DVD.


One of the biggest differences between DVDs and Blu-ray discs is storage capacity. While DVDs store between 4.7 and 8.5 gigabytes (GB) of data, Blu-ray discs store between 25 and 50 GB of data.


A DVD is read using a red laser while a Blu-ray is read using a blue laser, hence the latter's name. The Blu-ray's laser wavelength is 405 nanometers (nm), and the DVD's is 650 nm, which enables the Blu-ray disc to provide sharper images.

Data Transfer

The data transfer rate for a video/audio DVD is 10.08 (megabits per second0 Mbps and for a video/audio Blu-ray disc is 54 Mbps.


A Blu-ray disc's resolution is 1,920 by 1080 dots per inch (dpi) while a DVD's is 720 by 480 dpi. With its higher resolution and larger storage capacity, the Blu-ray disc can provide high-definition viewing.


A DVD and Blu-ray disc are identical in thickness (120mm), but each disc's protection coating is different. The DVD has a protection coating that is 0.6mm thick while the Blu-ray disc has one that is 0.1mm thick. In addition, the Blu-ray's coating is hard, while the DVDs is not.


A Blu-ray disc player is capable of playing a DVD, while a DVD player cannot play a Blu-ray disc.