Note	Frequency (Hz)	Wavelength (cm)
C0	16.05	2148.96
C#0/Db0	17.01	2028.35
D0	18.02	1914.50
D#0/Eb0	19.09	1807.05
E0	20.23	1705.63
F0	21.43	1609.90
F#0/Gb0	22.70	1519.54
G0	24.05	1434.26
G#0/Ab0	25.48	1353.76
A0	27.00	1277.78
A#0/Bb0	28.61	1206.06
B0	30.31	1138.37
C1	32.11	1074.48
C#1/Db1	34.02	1014.17
D1	36.04	957.25
D#1/Eb1	38.18	903.53
E1	40.45	852.81
F1	42.86	804.95
F#1/Gb1	45.41	759.77
G1	48.11	717.13
G#1/Ab1	50.97	676.88
A1	54.00	638.89
A#1/Bb1	57.21	603.03
B1	60.61	569.19
C2	64.22	537.24
C#2/Db2	68.04	507.09
D2	72.08	478.63
D#2/Eb2	76.37	451.76
E2	80.91	426.41
F2	85.72	402.47
F#2/Gb2	90.82	379.89
G2	96.22	358.56
G#2/Ab2	101.94	338.44
A2	108.00	319.44
A#2/Bb2	114.42	301.52
B2	121.23	284.59
C3	128.43	268.62
C#3/Db3	136.07	253.54
D3	144.16	239.31
D#3/Eb3	152.74	225.88
E3	161.82	213.20
F3	171.44	201.24
F#3/Gb3	181.63	189.94
G3	192.43	179.28
G#3/Ab3	203.88	169.22
A3	216.00	159.72
A#3/Bb3	228.84	150.76
B3	242.45	142.30
C4	256.87	134.31
C#4/Db4	272.14	126.77
D4	288.33	119.66
D#4/Eb4	305.47	112.94
E4	323.63	106.60
F4	342.88	100.62
F#4/Gb4	363.27	94.97
G4	384.87	89.64
G#4/Ab4	407.75	84.61
A4	432.00	79.86
A#4/Bb4	457.69	75.38
B4	484.90	71.15
C5	513.74	67.15
C#5/Db5	544.29	63.39
D5	576.65	59.83
D#5/Eb5	610.94	56.47
E5	647.27	53.30
F5	685.76	50.31
F#5/Gb5	726.53	47.49
G5	769.74	44.82
G#5/Ab5	815.51	42.30
A5	864.00	39.93
A#5/Bb5	915.38	37.69
B5	969.81	35.57
C6	1027.47	33.58
C#6/Db6	1088.57	31.69
D6	1153.30	29.91
D#6/Eb6	1221.88	28.24
E6	1294.54	26.65
F6	1371.51	25.15
F#6/Gb6	1453.07	23.74
G6	1539.47	22.41
G#6/Ab6	1631.01	21.15
A6	1728.00	19.97
A#6/Bb6	1830.75	18.84
B6	1939.61	17.79
C7	2054.95	16.79
C#7/Db7	2177.14	15.85
D7	2306.60	14.96
D#7/Eb7	2443.76	14.12
E7	2589.07	13.33
F7	2743.03	12.58
F#7/Gb7	2906.14	11.87
G7	3078.95	11.21
G#7/Ab7	3262.03	10.58
A7	3456.00	9.98
A#7/Bb7	3661.50	9.42
B7	3879.23	8.89
C8	4109.90	8.39
C#8/Db8	4354.29	7.92
D8	4613.21	7.48
D#8/Eb8	4887.52	7.06
E8	5178.15	6.66
F8	5486.06	6.29
F#8/Gb8	5812.28	5.94
G8	6157.89	5.60
G#8/Ab8	6524.06	5.29
A8	6912.00	4.99
A#8/Bb8	7323.01	4.71
B8	7758.46	4.45

http://www.roelhollander.eu/en/432-tuning/the-scale-of-fifths/

Fundamental Frequencies and Detecting Notes

using UnityEngine;
using System.Collections;

[RequireComponent(typeof(AudioSource))]
public class MicrophoneInput : MonoBehaviour {
  public float sensitivity = 100.0f;
  public float loudness = 0.0f;
  public float frequency = 0.0f;
  public int samplerate = 11024;

  void Start() {
    audio.clip = Microphone.Start(null, true, 10, samplerate);
    audio.loop = true; // Set the AudioClip to loop
    audio.mute = true; // Mute the sound, we don't want the player to hear it
    while (!(Microphone.GetPosition(AudioInputDevice) > 0)){} // Wait until the recording has started
    audio.Play(); // Play the audio source!
  }

  void Update(){
    loudness = GetAveragedVolume() * sensitivity;
    frequency = GetFundamentalFrequency();
  }

  float GetAveragedVolume()
  {
    float[] data = new float[256];
    float a = 0;
    audio.GetOutputData(data,0);
    foreach(float s in data)
    {
      a += Mathf.Abs(s);
    }
    return a/256;
  }

  float GetFundamentalFrequency()
  {
    float fundamentalFrequency = 0.0f;
    float[] data = new float[8192];
    audio.GetSpectrumData(data,0,FFTWindow.BlackmanHarris);
    float s = 0.0f;
    int i = 0;
    for (int j = 1; j < 8192; j++)
    {
      if ( s < data[j] )
      {
        s = data[j];
        i = j;
      }
    }
    fundamentalFrequency = i * samplerate / 8192;
    return fundamentalFrequency;
  }
}