Date and time

When you’re working with engineers, all they need is the time and date format length, and the i18n library API will format the date accordingly based on the locale signals Atlassian provides.

Each programming language has an i18n library that automatically localizes time and date strings based on a user’s locale settings/preferences. Date and time formatters are used to convert dates and times from their internal representations to textual form and back again in a language-independent manner.

Time and date strings should never be localized manually by a translator as time and date strings should be tied to a user’s locale (country and language) not their language. Hardcoding time and date content is bad practice and creates a bad international customer experience.

Use abbreviations when space is limited. Be clear about which months or days you are referring to.

Use these abbreviations for the days of the week:

• Monday – Mon

• Tuesday – Tue

• Wednesday – Wed

• Thursday – Thu

• Friday – Fri

• Saturday – Sat

• Sunday – Sun

Use these abbreviations for the months:

• January – Jan

• February – Feb

• March – Mar

• April – Apr

• May – leave it as May

• June – Jun

• July – Jul

• August – Aug

• September –  Sep

• October – Oct

• November – Nov

• December – Dec

Usually, the month comes before the day, then followed by the year. On the 8th day of the month of January, in the year 2020, then the date in American English can be written as:

• Jan 8

• January 8

• January 8, 2020

• Monday, January 8, 2020

Atlassian uses American English when writing in English. The formats above are broken down below to help when writing absolute values are required. Choose patterns that are appropriate for your context. 

Use full date in cards, bylines, and anywhere else space or your design allows for it:

• Use numerals for the day

• Spell out the month and day of the week in words

• Give the full four-digit year, not a two-digit abbreviation

Don’t use ordinal numbers, for example, 1st, 2nd, 3rd, etc.

You can also use a shorter format. Here spell out the month and use numerals for the day and year:

When space is limited shorten dates further, for example in lists, tables, charts, and comments.

• Spell out the month using abbreviations

• Use numerals for the day and the year

We recommend using the following pattern in most product copy if your context allows for it

When you need to leave out either the day or year, where possible, spell out the month in full.

• October 22 or July 2019

Writing dates entirely in numbers has disadvantages when it comes to readability and usability. This is because parts of the world use the date in a different order for numeric dates. Avoid doing this if it's possible because it often also has large UX implications. Instead, we recommend using any of the other date formats above.

If it’s absolutely necessary to express a date in numerical date format, use the format YYYY-MM-DD, and separate the elements by using hyphens. This conforms to ISO 8601 international standards for numerical date format.

• 2021-05-23

In a content draft or design spec if you’re adding a fictional date, choose a day greater than 12. This will help to clearly differentiate the day from the month.

Punctuation is a localization issue and should be localized wherever possible. Avoid if possible, defaulting to no punctuation.

When writing as numerals separate the numbers with an unspaced hyphen, using the format above.

Avoid using apostrophes. In more casual writing, you can use expressions such as ‘the seventies’ or 'the '70s' - using contractions for the missing numerals in the year.

Months and days are proper nouns and start with a capital letter. Specific days, times of the year or periods in history are all proper nouns. Use capitals for all proper nouns.

Use initial capitals for all institutional holidays, religious days, and public events:

• New Year’s Day

• Good Friday

• Ramadan

• Yom Kippur

Use ‘to’ if a number range is preceded by ‘from’ in a phrase. Use ‘and’ if a range is preceded by ‘between’. Avoid using hyphens and en dashes in spans of dates. 

When this isn't possible, for example:

• financial years

• or when information is in parentheses, such as terms of office and years of birth and death.

For these, use a hyphen without any spaces on either side:

• FY2008-09

• John Smith (1917–1992) had 3 younger siblings.

Spring in the northern hemisphere is autumn (fall) in the southern hemisphere. Avoid talking about seasons. Instead, use months or quarters.

In most cases, especially when you need to be precise, use numbers to give a clearer expression of time. Use a colon between the hours and minutes with no spaces on either side.

If it’s an exact hour, no “:00″ is required. For timestamps, labels on graphs, durations, and more avoid using zeros. Only show minutes if it’s not on the hour.

As with American English in most cases, we use rules set by the AP style guide.

• Lowercase a.m. and p.m., with periods.

• Use numerals, with a space between the time and the a.m. or p.m., for example, 6:30 a.m.

• If a time range is entirely in the morning or evening, use a.m. or p.m. only once: “6:30-10 p.m.” If it goes from the morning into the evening (or vice versa), you need both: “10 a.m.-2 p.m.”

Where possible use ‘noon’, ‘midday’ or ‘midnight’ instead of ‘12 a.m.’ or ‘12 p.m.’ to make it easier for people.

Use the 24-hour system if it helps people understand your content. But it’s important to understand that many times this is system-driven. This is important if you’re referring to time in the context of more serious communications, for example, in case of outages and in security comms.

The 24-hour system numbers hours from 00:00 hours (midnight) to 23:59 and always uses at least 4 digits. If seconds are included use 6 digits.

• The first 2 digits are the hours

• The next 2 digits are the minutes

• The last 2 digits are the seconds

Use a colon to separate the hours, minutes, and seconds.

Avoid using the prefix ‘bi’ to mean either 2 or twice. It can be confusing.

• ‘Bimonthly’ can mean either every 2 months or twice a month.

• ‘Biannual’ means twice a year.

Instead, use fortnightly or the phrase ‘every 2’.

This is used when displaying both the date and the time of day. For example, in historical versions of pages. To do this use the following formats

• MMM dd, yyyy HH:mm

• dd, HH:mm

It’s important that you express date and time information as you would speak in conversation when the situation allows for it.

In some cases, the easiest way to describe something that happened very recently is using the ‘ago’ format. Use this when the exact date is less important. For future and past events, use approximate time by rounding down to the largest or most recent date or time. 

You should always provide a way for people to see the actual timestamp, usually via a tooltip.

Date and time formatting differs greatly from country to country, and even within regions of a country, such as Canada and Switzerland.

The Product Internationalization team is responsible for creating product UI content in non-English languages by localizing externalized code strings provided by our Product Engineers.

In order to accurately localize date and time formatting for different locales (country and language), we require Engineers to ensure that all content containing the date and time references are not hardcoded and reference built-in i18n libraries/APIs for automatic format

The best practice for Internationalization is for Engineers not to hardcode time and date strings and to reference the programming i18n library API which will automatically format time and date strings as per the detected or selected locale.