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Swatch Internet Time is a concept introduced in 1998 and marketed by the Swatch corporation as an alternative, decimal measure of time. One of the goals was to simplify the way people in different time zones communicate about time, mostly by eliminating time zones altogether.


Instead of hours and minutes, the 24 hour day is divided up into 1000 parts called ".beats", each .beat being 1 minute and 26.4 seconds, and equal to the decimal minute introduced after the French Revolution. There are no time zones; instead, the new scale of Biel Mean Time (BMT) is used, based on the company's headquarters in Biel, Switzerland. Despite the name, BMT does not refer to mean solar timeat the Biel meridian, but is equivalent to Central European Time, or UTC+1. However, unlike the regular time in most countries, Swatch does not have daylight saving time and thus it matches the central European countries during winter and the United Kingdom during summer. If it were to use UTC, it would match the clock time in the UK during winter, but would not match any important territories during summer.

The most distinctive aspect of Swatch Internet Time is its notation; as an example, "@248" would indicate a time 248 .beats after midnight, equivalent to a fractional day of 0.248 CET, or 4:57:07.2 UTC. Although Swatch does not specify units smaller than one .beat, third party implementations have extended the standard by adding "centibeats" or "sub-beats" as a decimal fraction, for extended precision: @248.000. No explicit format was provided for dates, although the Swatch website displays the Gregorian calendar date in the order day-month-year, separated by periods and prefixed by the letter d (d31.01.99).

Like UTC, Internet time is the same throughout the world. For example, when the time is 875 .beats, or @875, in New York City, it is also @875 in Tokyo.

With its decimal character the time system is supposed to be more attractive for some people than the traditional Babylonian system of time units (24 hours of 60 minutes of 60 seconds). For example, if one learned some event took 5500 .beats to complete, it would be easy to see that it happened over five and a half days. But if one learned that an event took place over 132 hours, its duration in days would be less obvious. On the other hand, the system has been met with much criticism.


Swatch Internet Time appears to be more of a commercial marketing attempt than a usable system. Although there are advantages, the system has major drawbacks:

  • The use of Central European Time (UTC+1) to denote 0 .beats introduces an unwanted additional meridian (at 15°E); the Greenwich Meridian (UTC) is the standard international meridian. This can be corrected by using 'TermiSoc Time', devised by University of Plymouth Computing Society, which is a similar system working on UTC rather than Biel Time. However, the disadvantage with this system is that it runs with 1024 'bytes' in a day rather than 1000 'beats'.
  • The phrase "Biel Mean Time" is misleading, as there is no connection with any meridian that runs through Biel (which is at approximately 7°15'E), despite a "meridian" marked on the Swatch building.
  • The second, and not the .beat, is the basic SI unit of time measurement. The use of an additional time system adds unnecessary complexity for scientific calculations.
  • No submultiple units are specified, prompting divergent extensions by third parties. Officially the system is accurate to 1 minute and 26.4 seconds.
  • Noon is at different .beat in every time zone. For example in Helsinki it is noon at @417; in New York City, however, it is noon at @708. Sunrise and sunset are also very different. Thus, while the system would make it easier to arrange meetings etc. across time zones, there will always remain a need to convert to local time. But this is harder to compute than a conversion from UTC, which is already available as a common timeframe.
  • The system is a derivative of UTC, but specifies no accommodation for leap seconds.

Most Internet standards actually use either local civil time with a time zone indicator, or the global UTC time standard.


The timescale was announced on October 23, 1998, in a ceremony attended by Nicolas G. Hayek, President and CEO of the Swatch Group, G.N. Hayek, President of Swatch Ltd., and Nicholas Negroponte, founder and then-director of the MIT Media Lab.

During 1999, Swatch produced several models of watch that displayed Swatch Internet Time as well as standard time, and even convinced a few websites (such as to use the new format. The clock applet in the GNOME desktop can be set to display time in this manner. It is also used as a time reference on ICQ, and the online role-playing game Phantasy Star Online has used it since its launch on the Sega Dreamcast in 2000 to try to facilitate cross-continent gaming (as the game allowed Japanese, American and European players to mingle on the same servers). In March, 2001, Ericsson released the T20e, a mobile phone which gave the user the option of displaying Internet Time. No further Ericsson phones had this feature. Outside these areas, though, it appears to be infrequently used.

In early 1999, Swatch began a marketing campaign based around the launch of their Beatnik satellite for a set of Internet Time watches.

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