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MIDI Note Number to Frequency

 

MIDI Note Number to Frequency Conversion

 

The standard tuning pitch is A4 (A above middle C) 440 Hertz(Hz). When the octave is divided into 12 equally spaced pitches, then each interval between these pitches when they are arranged within the same octave in an ascending sequence is the equal-tempered semitone:

 

  21/12 =  1.059463094 . . .

 

 

The frequencies of equal-tempered pitches are easily calculated from any reference frequency according to :

 

                                 f = 2 n/12 fref

 

where n is the number of semitones between the reference frequency (fref), and the desired frequency, f .  

 

For example, the frequency of the equal-tempered pitch located a major third up (+4 semitones) from A440 is 440(24/12) = 554.365... Hz, while middle C, a major sixth down ( -9 semitones), has a frequency of 440(2-9/12) = 261.6255...Hz.

 

 

MIDI

Note

Frequency

MIDI

Note

Frequency

C 0 8.1757989156 12 16.3515978313
Db 1 8.6619572180 13 17.3239144361
D 2 9.1770239974 14 18.3540479948
Eb 3 9.7227182413 15 19.4454364826
E 4 10.3008611535 16 20.6017223071
F 5 10.9133822323 17 21.8267644646
Gb 6 11.5623257097 18 23.1246514195
G 7 12.2498573744 19 24.4997147489
Ab 8 12.9782717994 20 25.9565435987
A 9 13.7500000000 21 27.5000000000
Bb 10 14.5676175474 22 29.1352350949
B 11 15.4338531643 23 30.8677063285
 
C 24 32.7031956626 36 65.4063913251
Db 25 34.6478288721 37 69.2956577442
D 26 36.7080959897 38 73.4161919794
Eb 27 38.8908729653 39 77.7817459305
E 28 41.2034446141 40 82.4068892282
F 29 43.6535289291 41 87.3070578583
Gb 30 46.2493028390 42 92.4986056779
G 31 48.9994294977 43 97.9988589954
Ab 32 51.9130871975 44 103.8261743950
A 33 55.0000000000 45 110.0000000000
Bb 34 58.2704701898 46 116.5409403795
B 35 61.7354126570 47 123.4708253140
 
C 48 130.8127826503 60 261.6255653006
Db 49 138.5913154884 61 277.1826309769
D 50 146.8323839587 62 293.6647679174
Eb 51 155.5634918610 63 311.1269837221
E 52 164.8137784564 64 329.6275569129
F 53 174.6141157165 65 349.2282314330
Gb 54 184.9972113558 66 369.9944227116
G 55 195.9977179909 67 391.9954359817
Ab 56 207.6523487900 68 415.3046975799
A 57 220.0000000000 69 440.0000000000
Bb 58 233.0818807590 70 466.1637615181
B 59 246.9416506281 71 493.8833012561
 
C 72 523.2511306012 84 1046.5022612024
Db 73 554.3652619537 85 1108.7305239075
D 74 587.3295358348 86 1174.6590716696
Eb 75 622.2539674442 87 1244.5079348883
E 76 659.2551138257 88 1318.5102276515
F 77 698.4564628660 89 1396.9129257320
Gb 78 739.9888454233 90 1479.9776908465
G 79 783.9908719635 91 1567.9817439270
Ab 80 830.6093951599 92 1661.2187903198
A 81 880.0000000000 93 1760.0000000000
Bb 82 932.3275230362 94 1864.6550460724
B 83 987.7666025122 95 1975.5332050245
 
C 96 2093.0045224048 108 4186.009044809
Db 97 2217.4610478150 109 4434.922095630
D 98 2349.3181433393 110 4698.636286678
Eb 99 2489.0158697766 111 4978.031739553
E 100 2637.0204553030 112 5274.040910605
F 101 2793.8258514640 113 5587.651702928
Gb 102 2959.9553816931 114 5919.910763386
G 103 3135.9634878540 115 6271.926975708
Ab 104 3322.4375806396 116 6644.875161279
A 105 3520.0000000000 117 7040.000000000
Bb 106 3729.3100921447 118 7458.620234756
B 107 3951.0664100490 119 7902.132834658
 
C 120 8372.0180896192
Db 121 8869.8441912599
D 122 9397.2725733570
Eb 123 9956.0634791066
E 124 10548.0818212118
F 125 11175.3034058561
Gb 126 11839.8215267723
G 127 12543.8539514160