Appointments - Do you use the correct time and date format?

Clear, unambiguous dates and times prevent missed meetings, costly travel mistakes, and confusion across countries and time zones.

Think about this, is that 10th of May or 5th of October? Is it 6 am or 6 pm?

Dates - kill the ambiguity

People in different regions format the date in different ways:

Figure: 10/05/25 reads differently to Aussie, American and Chinese

Software can also misinterpret it. For example, entering 10/05/2025 on an Aussie laptop could be read as October 5th, 2025, if opened on an American system.

This is why you should avoid numeric-only formats... they can cause major confusion. To make it even clearer, include abbreviated weekdays with dates.

❌ Figure: Bad example - Use slashes on their own, it’s ambiguous

✅ Figure: Good example - Use "DD MMM YYYY" and include the abbreviated day of the week

Times - 24-hour or am/pm - both are fine (when used correctly!)

Use valid formats to avoid confusion - both 24-hour and 12-hour formats are universal when used correctly:

❌ Figure: Bad example - Incorrect or ambiguous times

✅ Figure: Good example - Correct formatting for time

Avoid the 12 am / 12 pm trap.

• Use "noon" or "midnight" to the end of the time instead of just 12:00. E.g., 12:00 noon.
• For boundaries (e.g., validity periods), avoid 00:00; use 00:01 for start and 23:59 for end (common airline practice) to remove doubt.

Figure: Will you attend this event on the night of the 14th or the 15th?

Always include a time zone for cross-location events: AEST (UTC+10), AEDT (UTC+11), PT (UTC–8), etc.

Extra tips

• Use leading zeros in 24-hour times: 09:05, not 9:5
• Don’t mix separators: use “:” for time, not “. “or “h.”
• Use “6 pm” with lowercase letters and a space for clear, modern, and style-guide-friendly time formatting
• It is recommended to use the ISO standard (YYYY-MM-DD) for your filenames, so they can be sorted in descending or ascending order by time
  • e.g., 2025-08-15-sprint-review-notes.md