IEC 80000-13:2025
(Main)Quantities and units - Part 13: Information science and technology
Quantities and units - Part 13: Information science and technology
IEC 80000-13:2025 specifies names, symbols and definitions for quantities and units used in information science and technology. Where appropriate, conversion factors are also given. Prefixes for binary multiples are also given. International Standard IEC 80000-13 has been prepared by IEC technical committee 25: Quantities and units in close cooperation with ISO/TC 12: Quantities and units.
This second edition cancels and replaces the first edition published in 2008. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
addition of new prefixes for binary multiples.
Grandeurs et unités - Partie 13: Science et technologies de l'information
L'IEC 80000-13:2025 spécifie les noms, les symboles et les définitions des grandeurs et unités utilisées dans la science et les technologies de l'information. Des facteurs de conversion sont également indiqués, s'il y a lieu. Des préfixes pour multiples binaires sont aussi donnés. La Norme internationale IEC 80000-13 a été établie par le comité d'études 25 de l’IEC: Grandeurs et unités, en collaboration étroite avec le comité technique 12 de l’ISO: Grandeurs et unités.
Cette seconde édition annule et remplace la première édition parue en 2008. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
ajout de nouveaux préfixes pour les multiples binaires.
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Standards Content (Sample)
IEC 80000-13
Edition 2.0 2025-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Quantities and units –
Part 13: Information science and technology
Grandeurs et unités –
Partie 13: Science et technologies de l'information
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IEC 80000-13
Edition 2.0 2025-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Quantities and units –
Part 13: Information science and technology
Grandeurs et unités –
Partie 13: Science et technologies de l'information
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 01.060; 01.040.35 ISBN 978-2-8327-0160-7
– 2 – IEC 80000-13:2025 © IEC 2025
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
0.1 Tables of quantities . 5
0.2 General . 5
0.3 Remark on units for quantities whose dimensional exponents are all equal to zero . 5
0.4 Numerical statements in this International Standard . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Prefixes for binary multiples . 17
Alphabetical index . 18
Bibliography . 20
Table 1 – Quantities and units in information science and technology . 7
Table 2 – Prefixes for binary multiples . 17
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
QUANTITIES AND UNITS –
Part 13: Information science and technology
FOREWORD
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such patent rights.
IEC 80000-13 has been prepared by IEC technical committee 25: Quantities and units in close
cooperation with ISO/TC 12 Quantities and units. It is an International Standard.
This second edition cancels and replaces the first edition published in 2008. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) addition of new prefixes for binary multiples.
– 4 – IEC 80000-13:2025 © IEC 2025
The text of this International Standard is based on the following documents:
Draft Report on voting
25/811/FDIS 25/823/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
A list of all parts in the ISO 80000 and IEC 80000 series, published under the general title
Quantities and units, can be found on the ISO and IEC websites.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
INTRODUCTION
0.1 Tables of quantities
In most cases, only one name and only one symbol for the quantity are given; where two or
more names or two or more symbols are given for one quantity and no special distinction is
made, they are on an equal footing. When two types of italic letters exist (for example as with
ϑ and θ; φ and φ; a and a; g and g), only one of these is given. This does not mean that the
other is not equally acceptable. It is recommended that such variants should not be given
different meanings. A symbol within parenthesis implies that it is a reserve symbol, to be used
when, in a particular context, the main symbol is in use with a different meaning.
0.2 General
The names of units for the corresponding quantities are given together with the international
symbols and the definitions. These unit names are language-dependent, but the symbols are
th
international and the same in all languages. For further information, see the SI Brochure (9
edition 2019, updated in 2024) from BIPM and ISO 80000-1.
The units are arranged in the following way:
• The coherent SI units are given first. The SI units have been adopted by the General
Conference on Weights and Measures (Conférence Générale des Poids et Mesures,
CGPM). The use of coherent SI units, and their decimal multiples and submultiples formed
with the SI prefixes are recommended, although the decimal multiples and submultiples are
not explicitly mentioned.
• Some non-SI units are then given, being those accepted by the International Committee for
Weights and Measures (Comité Internation
...
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