<PAGE>

                                                                    EXHIBIT 12.1

                                     VIATEL
                       RATIO OF EARNINGS TO FIXED CHARGES
<TABLE>
<CAPTION>
                                                FOR THE YEARS ENDED DECEMBER 31,
                               ------------------------------------------------------------------
                                                                                        PRO FORMA
                                 1995       1996       1997       1998        1999        1999
                               --------   --------   --------   ---------   ---------   ---------
                                                     (DOLLARS IN THOUSANDS)
<S>                            <C>        <C>        <C>        <C>         <C>         <C>
Earnings Section 229.503(d)(1)
  Net loss...................  $(28,476)  $(38,375)  $(43,044)  $(127,304)  $(217,836)  $(217,836)
  Fixed Charges..............     9,681     11,426     13,056      86,402     150,848     202,771
  Preferred Dividends........                                      (3,301)     (1,341)    (15,291)
  Interest--Capitalized......      (508)       (67)      (164)     (3,322)    (10,075)    (10,075)
                               --------   --------   --------   ---------   ---------   ---------
                               $(19,303)  $(27,016)  $(30,152)  $ (47,525)  $ (78,404)  $ (40,431)
                               ========   ========   ========   =========   =========   =========
Fixed Charges
  Section 229.503(d)(1)
  Interest--Expensed*........  $  8,856   $ 10,848   $ 12,450   $  79,177   $ 137,409   $ 175,382
  Interest--Capitalized......       508         67        164       3,322      10,075      10,075
  Preferred Dividends........                                       3,301       1,341      15,291
  Lease Expense..............       317        511        442         602       2,023       2,023
                               --------   --------   --------   ---------   ---------   ---------
                               $  9,681   $ 11,426   $ 13,056   $  86,402   $ 150,848   $ 202,771
                               ========   ========   ========   =========   =========   =========
Ratio of Earnings to Fixed
  Charges....................     (1.99)     (2.36)     (2.31)      (0.55)      (0.52)      (0.20)
                               ========   ========   ========   =========   =========   =========
Deficiency of Earnings to
  Fixed Charges..............  $(28,984)  $(38,442)  $(43,208)  $(133,927)  $(229,252)  $(243,202)
                               ========   ========   ========   =========   =========   =========

<CAPTION>
                                  FOR THE SIX MONTHS ENDED JUNE 30,
                               --------------------------------------
                                                           PRO FORMA
                                  1999         2000          2000
                               ----------   -----------   -----------
                                       (DOLLARS IN THOUSANDS)
<S>                            <C>          <C>           <C>
Earnings Section 229.503(d)(1)
  Net loss...................   $(82,596)    $(253,848)    $(253,848)
  Fixed Charges..............     68,592       127,498       142,925
  Preferred Dividends........     (1,341)      (11,726)      (15,640)
  Interest--Capitalized......     (4,690)      (10,708)      (10,708)
                                --------     ---------     ---------
                                $(20,035)    $(148,784)    $(137,271)
                                ========     =========     =========
Fixed Charges
  Section 229.503(d)(1)
  Interest--Expensed*........   $ 61,665     $ 102,594     $ 114,107
  Interest--Capitalized......      4,690        10,708        10,708
  Preferred Dividends........      1,341        11,726        15,640
  Lease Expense.............         896         2,470         2,470
                                --------     ---------     ---------
                                $ 68,592     $ 127,498     $ 142,925
                                ========     =========     =========
Ratio of Earnings to Fixed
  Charges....................      (0.29)        (1.17)        (0.96)
                                ========     =========     =========
Deficiency of Earnings to
  Fixed Charges..............   $(88,627)    $(276,282)    $(280,196)
                                ========     =========     =========
</TABLE>

------------------------

*   Includes accretion of senior discount notes and amortization of debt issue
    costs.

**  The ratio of combined fixed charges and preferred stock dividends to
    earnings is calculated as fixed charges divided by earnings. Fixed charges
    consist of interest on indebtedness, dividends on preferred stock and one-
    third of rent expense. Earnings were not sufficient to cover fixed charges
    by $29.0 million, $38.4 million, $43.2 million, $133.9 million, $229.3
    million, $88.6 million, $276.3 million, $243.2 million, and $280.2 million
    for the years ended December 31, 1995, 1996, 1997, 1998, and 1999, and for
    the six months ended June 30, 1999 and 2000 and pro forma for the year
    ended December 31, 1999 and for the six months ended June 30, 2000,
    respectively.