Template documentationReturns the input if it is a valid date, empty string if not.
Usage
{{Template:Welcome needed/valid date|date}}
Parameters
There is one required parameter:
|1=– the date; expected format is:dd Monthname YYYY, but any format recognized by {{date}} is permitted.
Examples
{{Template:Welcome needed/valid date|29 August 2025}}→ 29 August 2025{{Template:Welcome needed/valid date|2025-08-29}}→ 2025-08-29{{Template:Welcome needed/valid date|25 January 202A}}→ (returns empty for invalid year ){{Template:Welcome needed/valid date|25 Octember 2021}}→ (returns empty for invalid month ){{Template:Welcome needed/valid date|29 February 2023}}→ 29 February 2023 !! (because {{date|2023-02-29|DMY}} -> '1 March 2024' ){{Template:Welcome needed/valid date|29 February 2024}}→ 29 February 2024
Technical note
Current behavior is the 29 February is never rejected for non-leap years (and neither is 30 February or 31 February). This is due to bizarre behavior of {{date}}, which 'fixes' dates up to {{date|2023-02-31|DMY}} → 3 March 2023, but not dates of {{date|2023-02-32|DMY}} → 2023-02-32 or larger, which simply return the input for invalid dates. The subtemplate will have to be adjusted for this weird behavior.