<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
CONSOLIDATED FINANCIAL STATEMENTS IN THE ANNUAL REPORT ON FORM 10-K OF CMGI,
INC. FOR THE PERIOD ENDED JULY 31, 2000 AND JULY 31, 1999 AND IS QUALIFIED IN
ITS ENTIRETRY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.

<MULTIPLIER> 1,000

                                                  
<PERIOD-TYPE>                   12-MOS                   12-MOS
<FISCAL-YEAR-END>                          JUL-31-2000             JUL-31-1999
<PERIOD-START>                             AUG-01-1999             AUG-01-1998
<PERIOD-END>                               JUL-31-2000             JUL-31-1999
<CASH>                                         639,666                 468,912
<SECURITIES>                                 1,595,011               1,532,327
<RECEIVABLES>                                  232,104                  41,794
<ALLOWANCES>                                    34,618                   3,034
<INVENTORY>                                          0                       0
<CURRENT-ASSETS>                             2,571,875               2,057,334
<PP&E>                                         259,270                  24,832
<DEPRECIATION>                                       0                       0
<TOTAL-ASSETS>                               8,557,107               2,404,594
<CURRENT-LIABILITIES>                        1,461,770                 676,329
<BONDS>                                              0                       0
<PREFERRED-MANDATORY>                          383,140                 411,283
<PREFERRED>                                          0                       0
<COMMON>                                         2,965                   1,912
<OTHER-SE>                                   5,782,837               1,060,549
<TOTAL-LIABILITY-AND-EQUITY>                 8,557,107               2,404,594
<SALES>                                        898,050                 186,389
<TOTAL-REVENUES>                               898,050                 186,389
<CGS>                                          737,264                 179,553
<TOTAL-COSTS>                                  737,264                 179,553
<OTHER-EXPENSES>                             2,350,593                 133,495
<LOSS-PROVISION>                                     0                       0
<INTEREST-EXPENSE>                              56,617                   4,371
<INCOME-PRETAX>                            (1,485,866)                 749,245
<INCOME-TAX>                                 (121,173)                 325,402
<INCOME-CONTINUING>                        (1,364,693)                 423,843
<DISCONTINUED>                                       0                  52,397
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                               (1,364,693)                 476,240
<EPS-BASIC>                                     (5.26)                    2.54
<EPS-DILUTED>                                   (5.26)                    2.30