February 31
Also known as 31 February, February 31st, 31st of February, Feb 31
fictional date
~9 min read
Article
February 31 on a tombstone Several non-standard dates are used in calendars for various purposes: some are expressly fictional, some are intended to produce a rhetorical effect (such as sarcasm), and others attempt to address a particular mathematical, scientific or accounting requirement or discrepancy within the calendar system.
Historical