> For the complete documentation index, see [llms.txt](https://docs.bluestorm.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.bluestorm.io/checks/microflow/mf_0001.md). # Incorrect date format

Check ID	MF_0001
Category	Quality
Summary	Mendix uses letter patterns for formatting date strings. The letters used when configuring these patterns can be confusing. This can lead to dates that are incorrectly formatted. This check looks for common mistakes made when configuring date formats.
Options	This check does not have any options.
Pass	Date format expressions in your microflow do not contain any common mistakes.
Fail	Date format expressions in your microflow contain common mistakes such as (all examples below show FAIL conditions): Day of year should not be used in parse/format date time functions `parseDateTime('2015-05-21', 'yyyy-MM-DD')` Hour format should be specified correctly in parse/format date-time functions `parseDateTime('13:37', 'hh:mm')` MM and mm tokens should be used correctly in parse/format date-time functions `parseDateTime('2015-05-21', 'yyyy-mm-dd')` `parseDateTime('13:37', 'HH:MM')` Seconds token should be specified correctly in parse/format date-time functions `parseDateTime('13:37:01', 'HH:mm:SS')` Week year should not be used in date formatting or parsing `parseDateTime($Var, 'YYYY')` AM/PM indicator should only be used in combination with lowercase “h” `formatDateTime($DateTime, 'H:mm a')`

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