Il numero romano MCCCIII nel sistema decimale vale: 1303.
MCCCIII in latino si scrive mille trecenti tres,
mentre in italiano milletrecentotré.
MCCLXXXIV, MCCLXXXV, MCCLXXXVI, MCCLXXXVII, MCCLXXXVIII, MCCLXXXIX, MCCXC, MCCXCI, MCCXCII, MCCXCIII, MCCXCIV, MCCXCV, MCCXCVI, MCCXCVII, MCCXCVIII, MCCXCIX, MCCC, MCCCI, MCCCII, MCCCIV, MCCCV, MCCCVI, MCCCVII, MCCCVIII, MCCCIX, MCCCX, MCCCXI, MCCCXII, MCCCXIII, MCCCXIV, MCCCXV, MCCCXVI, MCCCXVII, MCCCXVIII, MCCCXIX, MCCCXX, MCCCXXI, MCCCXXII