There were times, and it is not so long ago, when not even Europe had a unified calendar – not to mention the world. And although the IT revolution made us unify most of the information to 0 and 1, including all everyday thing, calendar dates can still turn into a real pain when it comes to localization.

Calendar dates formatting

There are various formats that different languages and cultures use for writing dates. The reason for such usage of the specific formats are usually historic and cultural, but some are also driven by technical development. The calendar dates can vary as follows:

• Order of date components (e.g. day-month-year = little-endian; month-day-year = middle-endian; year-month-day = big-endian) - the most popular in the majority of countries around the world is the day-month-year format, mainly due to the Western religious and legal customs of writing dates (e.g. the 1st day of November, Anno Domini 2016)
• Usage of leading zeros in days and months (e.g. 01-01-2016 vs. 1-1-2016) – German-speaking and German-influenced regions, for instance, tend to use
• Separators like hyphens, dots, etc. (e.g. 01-01-2016, 01.01.2016, 1 January 2016, 1. January 2016 or 01/01/2016)
• Year format (e.g. 01-01-2016 vs. 01-01-16)
• Numeral type usage – Arabic vs. Roman (e.g. 1. XII. 2016 vs. 1.12.2016)
• Months name usage (months can be written down using both names and numbers, e.g. 1.1.2016 vs. 1.January 2016)
• Other language or cultural specifics (e.g. 1st January 2016 in English, or adding AD (Anno Domini), or CE (common era) to the date)
• Reversed day and month this is a popular format used only in the United States and often a default settings in many computers, e.g. 01-31-2016 for January 31, 2016.

There is also an ISO 8601 standard for data elements and interchange formats, that works with YYYY-MM-DD format.

Time zones matter in dates localization

Not only the formatting, but also timezones need to be taken into consideration, based on the observer's view. This can be rather tricky with important historical dates, where e.g. the attack on Pearl Harbor, generally known to be December 7th, 1941, actually took place on December 8th in Japanese time.