Foolscap or fool’s cap may refer to:

• Foolscap folio, a paper size of 8+1⁄2 × 13+1⁄2 inches (216 × 343 mm)
• Foolscap, a paper size of 17 × 13+1⁄2 inches (432 × 343 mm)
• Foolscap, a book by Michael Malone
• Fool’s cap, a cap with bells worn by court jesters

• Cortinarius orellanus, also known as fool’s webcap, a poisonous mushroom
• List of Dinosaur King characters