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                              ALLAIRE CORPORATION
                                   EXHIBIT 11
       STATEMENT RE: COMPUTATION OF UNAUDITED NET INCOME (LOSS) PER SHARE
 AND PRO FORMA NET INCOME (LOSS) PER SHARE (IN THOUSANDS, EXCEPT PER SHARE DATA)



<TABLE>
<CAPTION>

                                                    THREE MONTHS ENDED   SIX MONTHS ENDED
                                                         JUNE 30,           JUNE 30,
                                                    ------------------  -----------------
                                                     2000      1999      2000       1999
                                                    -------   -------   -------   -------
<S>                                                   <C>      <C>        <C>      <C>
BASIC:
    Net income (loss)                                 1,785    (2,913)    2,776    (5,529)
                                                    -------   -------   -------   -------
    Weighted average common shares outstanding       27,105    22,744    26,997    20,899
                                                    -------   -------   -------   -------
    Basic net income (loss) per share               $  0.07   $ (0.13)  $  0.10   $ (0.26)
                                                    =======   =======   =======   =======

DILUTED:
    Net income (loss)                                 1,785    (2,913)    2,776    (5,529)
                                                    -------   -------   -------   -------
        Weighted average common shares outstanding   27,105    22,744    26,997    20,899
        Weighted common stock equivalents             3,848         -     4,135         -
                                                    -------   -------   -------   -------
    Total weighted average shares                    30,953    22,744    31,132    20,899

    Diluted net income (loss) per share             $  0.06   $ (0.13)  $  0.09   $ (0.26)
                                                    =======   =======   =======   =======

</TABLE>


<TABLE>
<CAPTION>
                                                                                SIX MONTHS ENDED
                                                                                 JUNE 30, 1999
                                                                                -----------------
<S>                                                                                 <C>
PRO FORMA BASIC:
    Net income (loss)                                                               (5,529)
                                                                                   -------
        Pro forma weighted average common shares outstanding (1)                    20,933
        Shares attributable to the assumed conversion of convertible
            preferred stock upon closing of the initial public offering                898
                                                                                   -------
    Total pro forma weighted average shares outstanding                             21,831

    Pro forma basic net income (loss) per share                                    $ (0.25)
                                                                                   =======
PRO FORMA DILUTED:
    Net income (loss)                                                               (5,529)
                                                                                   -------
        Pro forma weighted average common shares outstanding (1)                    20,933
        Shares attributable to the assumed conversion of convertible
            preferred stock upon closing of the initial public offering                898
                                                                                   -------
    Total pro forma weighted average shares                                         21,831

    Pro forma diluted net income (loss) per share                                  $ (0.25)
                                                                                   =======
</TABLE>


(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.