MIDI Note Number to Frequency Conversion Chart

    MIDI                 MIDI                   MIDI
    Note   Frequency     Note   Frequency       Note   Frequency
 C  0    8.1757989156    12    16.3515978313    24    32.7031956626
 Db 1    8.6619572180    13    17.3239144361    25    34.6478288721
 D  2    9.1770239974    14    18.3540479948    26    36.7080959897
 Eb 3    9.7227182413    15    19.4454364826    27    38.8908729653
 E  4   10.3008611535    16    20.6017223071    28    41.2034446141
 F  5   10.9133822323    17    21.8267644646    29    43.6535289291
 Gb 6   11.5623257097    18    23.1246514195    30    46.2493028390
 G  7   12.2498573744    19    24.4997147489    31    48.9994294977
 Ab 8   12.9782717994    20    25.9565435987    32    51.9130871975
 A  9   13.7500000000    21    27.5000000000    33    55.0000000000
 Bb 10  14.5676175474    22    29.1352350949    34    58.2704701898
 B  11  15.4338531643    23    30.8677063285    35    61.7354126570

 C  36  65.4063913251    48   130.8127826503    60   261.6255653006
 Db 37  69.2956577442    49   138.5913154884    61   277.1826309769
 D  38  73.4161919794    50   146.8323839587    62   293.6647679174
 Eb 39  77.7817459305    51   155.5634918610    63   311.1269837221
 E  40  82.4068892282    52   164.8137784564    64   329.6275569129
 F  41  87.3070578583    53   174.6141157165    65   349.2282314330
 Gb 42  92.4986056779    54   184.9972113558    66   369.9944227116
 G  43  97.9988589954    55   195.9977179909    67   391.9954359817
 Ab 44  103.8261743950   56   207.6523487900    68   415.3046975799
 A  45  110.0000000000   57   220.0000000000    69   440.0000000000
 Bb 46  116.5409403795   58   233.0818807590    70   466.1637615181
 B  47  123.4708253140   59   246.9416506281    71   493.8833012561

 C  72  523.2511306012   84  1046.5022612024    96  2093.0045224048
 Db 73  554.3652619537   85  1108.7305239075    97  2217.4610478150
 D  74  587.3295358348   86  1174.6590716696    98  2349.3181433393
 Eb 75  622.2539674442   87  1244.5079348883    99  2489.0158697766
 E  76  659.2551138257   88  1318.5102276515   100  2637.0204553030
 F  77  698.4564628660   89  1396.9129257320   101  2793.8258514640
 Gb 78  739.9888454233   90  1479.9776908465   102  2959.9553816931
 G  79  783.9908719635   91  1567.9817439270   103  3135.9634878540
 Ab 80  830.6093951599   92  1661.2187903198   104  3322.4375806396
 A  81  880.0000000000   93  1760.0000000000   105  3520.0000000000
 Bb 82  932.3275230362   94  1864.6550460724   106  3729.3100921447
 B  83  987.7666025122   95  1975.5332050245   107  3951.0664100490

 C  108 4186.0090448096  120  8372.0180896192
 Db 109 4434.9220956300  121  8869.8441912599
 D  110 4698.6362866785  122  9397.2725733570
 Eb 111 4978.0317395533  123  9956.0634791066
 E  112 5274.0409106059  124 10548.0818212118
 F  113 5587.6517029281  125 11175.3034058561
 Gb 114 5919.9107633862  126 11839.8215267723
 G  115 6271.9269757080  127 12543.8539514160
 Ab 116 6644.8751612791
 A  117 7040.0000000000
 Bb 118 7458.6201842894
 B  119 7902.1328200980
Note: Middle C is note #60. Frequency is in Hertz.


Here's a BASIC program to calculate an array with all of the above frequencies (ie, so that MIDI(0), which pertains to note #0, is assigned the value of 8.1757989156). Tuning is based upon A=440.

DIM MIDI(127)
A=440
FOR x = 0 to 127
MIDI(x) = (A / 32) * (2 ^ ((x - 9) / 12))
NEXT x
If you plan to always use 440 tuning, then you can use this simplified code instead:
DIM MIDI(127)
FOR x = 0 to 127
MIDI(x) = 8.1758 * 2^(x/12)
NEXT x