30th is the ordinal form of the number 30. 30th or Thirtieth may also refer to:
A fraction, , equal to one of 30 equal parts 30th of the month, a recurring calendar date
Geography 30th meridian east, a line of longitude 30th meridian west, a line of longitude 30th parallel north, a circle of latitude 30th parallel south, a circle of latitude 30th Street (disambiguation) 30th Street station (disambiguation)
Military 30th Army (disambiguation) 30th Battalion (disambiguation) 30th Brigade (disambiguation) 30th Division (disambiguation) 30th Regiment (disambiguation) 30th Squadron (disambiguation)
Other "The 30th", 2022 song by American singer-songwriter Billie Eilish on the album Guitar Songs Thirtieth Amendment 30th century 30th century BC
See also 30 (disambiguation) The Thirtieth Piece of Silver, lost 1920 American silent drama film