Designation | Sides | Layers (total) | Diameter | Capacity | ||
---|---|---|---|---|---|---|
(cm) | (GB) | (GiB) | ||||
DVD-1[21] | SS SL | 1 | 1 | 8 | 1.46 | 1.36 |
DVD-2 | SS DL | 1 | 2 | 8 | 2.66 | 2.47 |
DVD-3 | DS SL | 2 | 2 | 8 | 2.92 | 2.72 |
DVD-4 | DS DL | 2 | 4 | 8 | 5.32 | 4.95 |
DVD-5 | SS SL | 1 | 1 | 12 | 4.70 | 4.38 |
DVD-9 | SS DL | 1 | 2 | 12 | 8.54 | 7.95 |
DVD-10 | DS SL | 2 | 2 | 12 | 9.40 | 8.75 |
DVD-14[22] | DS DL/SL | 2 | 3 | 12 | 13.24 | 12.33 |
DVD-18 | DS DL | 2 | 4 | 12 | 17.08 | 15.90 |
Designation | Sides | Layers (total) | Diameter | Capacity | ||
---|---|---|---|---|---|---|
(cm) | (GB) | (GiB) | ||||
DVD-R | SS SL (1.0) | 1 | 1 | 12 | 3.95 | 3.68 |
DVD-R | SS SL (2.0) | 1 | 1 | 12 | 4.70 | 4.37 |
DVD-RW | SS SL | 1 | 1 | 12 | 4.70 | 4.37 |
DVD+R | SS SL | 1 | 1 | 12 | 4.70 | 4.37 |
DVD+RW | SS SL | 1 | 1 | 12 | 4.70 | 4.37 |
DVD-R | DS DL | 2 | 2 | 12 | 9.40 | 8.75 |
DVD-RW | DS DL | 2 | 2 | 12 | 9.40 | 8.75 |
DVD+R | DS DL | 2 | 2 | 12 | 9.40 | 8.75 |
DVD+RW | DS DL | 2 | 2 | 12 | 9.40 | 8.75 |
DVD-RAM | SS SL | 1 | 1 | 8 | 1.46 | 1.36* |
DVD-RAM | DS DL | 2 | 2 | 8 | 2.65 | 2.47* |
DVD-RAM | SS SL (1.0) | 1 | 1 | 12 | 2.58 | 2.40 |
DVD-RAM | SS SL (2.0) | 1 | 1 | 12 | 4.70 | 4.37 |
DVD-RAM | DS DL (1.0) | 2 | 2 | 12 | 5.16 | 4.80 |
DVD-RAM | DS DL (2.0) | 2 | 2 | 12 | 9.40 | 8.75* |
The basic types of DVD (12 cm diameter, single-sided or homogenous double-sided) are referred to by a rough approximation of their capacity in gigabytes. In draft versions of the specification, DVD-5 indeed held five gigabytes, but some parameters were changed later on as explained above, so the capacity decreased. Other formats, those with 8 cm diameter and hybrid variants, acquired similar numeric names with even larger deviation.
The 12 cm type is a standard DVD, and the 8 cm variety is known as a MiniDVD. These are the same sizes as a standard CD and a mini-CD, respectively. The capacity by surface (MiB/cm2) varies from 6.92 MiB/cm2 in the DVD-1 to 18.0 MiB/cm2 in the DVD-18.
As with hard disk drives, in the DVD realm, gigabyte and the symbol GB are usually used in the SI sense (i.e., 109, or 1,000,000,000 bytes). For distinction, gibibyte (with symbol GiB) is used (i.e., 230, or 1,073,741,824 bytes). Most computer operating systems display file sizes in gibibytes, mebibytes, and kibibytes, labeled as gigabyte, megabyte, and kilobyte, respectively.
Each DVD sector contains 2,418 bytes of data, 2,048 bytes of which are user data. There is a small difference in storage space between + and - (hyphen) formats:
Type | Sectors | Bytes | MB | MiB | GB | GiB |
---|---|---|---|---|---|---|
DVD−R SL | 2,298,496 | 4,707,319,808 | 4,707.320 | 4,489.250 | 4.707 | 4.384 |
DVD+R SL | 2,295,104 | 4,700,372,992 | 4,700.373 | 4,482.625 | 4.700 | 4.378 |
DVD−R DL | 4,171,712 | 8,543,666,176 | 8,543.666 | 8,147.875 | 8.544 | 7.957 |
DVD+R DL | 4,173,824 | 8,547,991,552 | 8,547.992 | 8,152.000 | 8.548 | 7.96 |
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