A new and distinct cultivar of Caladium plant named ‘ARN BRZ OF14-40’, characterized by its tall and upright to somewhat mounding plant habit; dense and bushy appearance; vigorous growth habit and moderate growth rate; fancy-type leaves that are pale green or pale greenish yellow in color and flushed with reddish bronze, with reddish bronze-colored margins, and midvein and primary veins that are greenish white tinged with reddish bronze in color surrounded by white areas; occasional dark green-colored flecks and/or blotches may be present; and petioles that are almost black in color with greenish or tan-colored stripes.