What is being measured?
Nominal disc size covered by ECMA-130. It excludes mini discs and is not the diameter of the central hole.
Use the named object, variant and dimension. A manufactured or natural object can differ from this reference.
- Dimension
- nominal disc diameter
- Reference value
- 120 mm
- Evidence
- Nominal standard size
- In metres
- 0.120 m
- Variant
- 120 mm CD-ROM; ECMA-130 second edition
Put the length in perspective
One Standard CD-ROM disc represents approximately 1.4 card lengths measured end to end. This is a length ratio; it does not calculate how the objects pack or fit.
Standard CD-ROM disc · 0.120 m
Metre · 1 m
Foot (international) · 0.3048 m