Exhibit 11 ALLAIRE CORPORATION EXHIBIT 11 STATEMENT RE: COMPUTATION OF UNAUDITED NET LOSS PER SHARE AND PRO FORMA NET LOSS PER SHARE (IN THOUSANDS, EXCEPT PER SHARE DATA) ----------------------------------------------------------------------- THREE MONTHS ENDED SIX MONTHS ENDED JUNE 30, JUNE 30, 1999 1998 1999 1998 ------- ------- ------- ------- Basic and diluted net loss per share: Net loss ................................................... (2,913) (3,821) (5,529) (7,886) ------- ------- ------- ------- Basic and diluted weighted average common shares outstanding 11,372 3,512 10,449 3,317 ------- ------- ------- ------- Basic and diluted net loss per share ....................... $ (0.26) $ (1.09) $ (0.53) $ (2.38) ------- ------- ------- ------- THREE MONTHS ENDED SIX MONTHS ENDED JUNE 30, JUNE 30, 1999 1998 1999 1998 ------- ------- ------- ------- Pro forma basic and diluted net loss per share: Net loss ............................................................. (2,913) (3,821) (5,529) (7,886) ------- ------- ------- ------- Pro forma basic and diluted weighted average shares outstanding: Shares attributable to common stock (1) ............................ 11,372 3,937 10,467 3,785 Shares attributable to the assumed conversion of convertible preferred stock upon closing of the initial public offering ...... -- 3,817 449 3,817 ------- ------- ------- ------- Pro forma basic and diluted weighted average shares outstanding ...... 11,372 7,754 10,916 7,602 ------- ------- ------- ------- Pro forma basic and diluted loss per share ........................... $ (0.26) $ (0.49) $ (0.51) $ (1.04) ------- ------- ------- ------- (1) Includes outstanding common stock subject to repurchase under a stock restriction agreement which lapsed upon the consummation of the initial public offering in January 1999. 21