Note Frequency Chart

Q: What is the frequency of middle C (C4)?

Middle C is C4, which has a frequency of 261.63 Hz. It is MIDI note number 60. Middle C is the reference point for the piano keyboard and is the C note closest to the center of a standard 88-key piano.

Q: What frequency is A4?

A4 is 440 Hz, which is the international standard tuning pitch (ISO 16, 1955). It is MIDI note number 69. A4 is the A note above middle C (C4) and is used as the reference pitch for tuning orchestras and instruments worldwide.

Q: What are the 808 bass note frequencies?

808 bass notes typically live in the C1-B2 range: C1 = 32.70 Hz, D1 = 36.71 Hz, E1 = 41.20 Hz, F1 = 43.65 Hz, G1 = 49.00 Hz, A1 = 55.00 Hz, B1 = 61.74 Hz, C2 = 65.41 Hz, D2 = 73.42 Hz, E2 = 82.41 Hz, F2 = 87.31 Hz, G2 = 98.00 Hz, A2 = 110.00 Hz, B2 = 123.47 Hz. Tune your 808 to the root note of your track key.

Q: How do I convert MIDI note numbers to Hz?

Use the formula: Hz = 440 x 2^((MIDI - 69) / 12). For example, MIDI 60 (middle C): 440 x 2^((60-69)/12) = 440 x 2^(-0.75) = 261.63 Hz. Or use the free Note Frequency Calculator at notes.beatkey.app to look up any note instantly.

Complete Hz reference for all 128 MIDI notes. Find the exact frequency for any note from C-1 (8.18 Hz) to G9 (12,543 Hz). Includes piano range, 808 bass reference, and enharmonic equivalents.

128

Total MIDI notes

MIDI 0-127

88 keys

Standard piano range

A0 to C8

A4 = 440 Hz

Standard tuning

ISO 16 standard

10+ octaves

Octave span

C-1 to G9

808 Bass Frequency Reference

808s and sub-bass elements live in the C1-B2 range (MIDI 24-47). Tune your 808 to the root note of your track key for tight low-end. Use octave 1 for sub-heavy trap, octave 2 for more audible bass.

Note	Enharmonic	MIDI	Hz	Use
C1	-	24	32.70 Hz	Sub bass, deep kick
C#1	Db1	25	34.65 Hz	Sub bass, deep kick
D1	-	26	36.71 Hz	Sub bass, deep kick
D#1	Eb1	27	38.89 Hz	Sub bass, deep kick
E1	-	28	41.20 Hz	Sub bass, deep kick
F1	-	29	43.65 Hz	Sub bass, deep kick
F#1	Gb1	30	46.25 Hz	Sub bass, deep kick
G1	-	31	49.00 Hz	Sub bass, deep kick
G#1	Ab1	32	51.91 Hz	Sub bass, deep kick
A1	-	33	55.00 Hz	Sub bass, deep kick
A#1	Bb1	34	58.27 Hz	Sub bass, deep kick
B1	-	35	61.74 Hz	Sub bass, deep kick
C2	-	36	65.41 Hz	Bass guitar, melodic 808
C#2	Db2	37	69.30 Hz	Bass guitar, melodic 808
D2	-	38	73.42 Hz	Bass guitar, melodic 808
D#2	Eb2	39	77.78 Hz	Bass guitar, melodic 808
E2	-	40	82.41 Hz	Bass guitar, melodic 808
F2	-	41	87.31 Hz	Bass guitar, melodic 808
F#2	Gb2	42	92.50 Hz	Bass guitar, melodic 808
G2	-	43	98.00 Hz	Bass guitar, melodic 808
G#2	Ab2	44	103.83 Hz	Bass guitar, melodic 808
A2	-	45	110.00 Hz	Bass guitar, melodic 808
A#2	Bb2	46	116.54 Hz	Bass guitar, melodic 808
B2	-	47	123.47 Hz	Bass guitar, melodic 808

Frequency Ranges by Role

Understanding which frequencies map to which musical roles helps with mixing, EQ decisions, and production workflows.

Sub bass / deep kick fundamental

20-60 Hz - MIDI 24-34

C1 (32.70 Hz), E1 (41.20 Hz), G1 (49.00 Hz)

808 bass / bass guitar root

60-130 Hz - MIDI 35-47

C2 (65.41 Hz), G2 (98.00 Hz), B2 (123.47 Hz)

Bass guitar / cello low

130-250 Hz - MIDI 48-59

C3 (130.81 Hz), A3 (220.00 Hz)

Guitar body / vocals low end

250-500 Hz - MIDI 60-71

C4 middle C (261.63 Hz), A4 (440.00 Hz)

Vocals / piano main range

500 Hz-1 kHz - MIDI 72-83

C5 (523.25 Hz), A5 (880.00 Hz)

Strings / upper harmonics

1-4 kHz - MIDI 84-107

C6 (1046.5 Hz), A6 (1760.0 Hz)

Hi-hats / cymbals / air

4-20 kHz - MIDI 108+

C8 (4186.0 Hz) and above

Chromatic Scale by Octave

Full 12-note chromatic scale for each octave. Natural notes shown in white; sharps/flats in gray. Highlighted C notes mark each new octave.

Note	Alt	MIDI	Oct	Frequency (Hz)	kHz
C0		12	0	16.35
C#0	Db0	13	0	17.32
D0		14	0	18.35
D#0	Eb0	15	0	19.45
E0		16	0	20.60
F0		17	0	21.83
F#0	Gb0	18	0	23.12
G0		19	0	24.50
G#0	Ab0	20	0	25.96
A0		21	0	27.50
A#0	Bb0	22	0	29.14
B0		23	0	30.87
C1		24	1	32.70
C#1	Db1	25	1	34.65
D1		26	1	36.71
D#1	Eb1	27	1	38.89
E1		28	1	41.20
F1		29	1	43.65
F#1	Gb1	30	1	46.25
G1		31	1	49.00
G#1	Ab1	32	1	51.91
A1		33	1	55.00
A#1	Bb1	34	1	58.27
B1		35	1	61.74
C2		36	2	65.41
C#2	Db2	37	2	69.30
D2		38	2	73.42
D#2	Eb2	39	2	77.78
E2		40	2	82.41
F2		41	2	87.31
F#2	Gb2	42	2	92.50
G2		43	2	98.00
G#2	Ab2	44	2	103.83
A2		45	2	110.00
A#2	Bb2	46	2	116.54
B2		47	2	123.47
C3		48	3	130.81
C#3	Db3	49	3	138.59
D3		50	3	146.83
D#3	Eb3	51	3	155.56
E3		52	3	164.81
F3		53	3	174.61
F#3	Gb3	54	3	185.00
G3		55	3	196.00
G#3	Ab3	56	3	207.65
A3		57	3	220.00
A#3	Bb3	58	3	233.08
B3		59	3	246.94
C4		60	4	261.63
C#4	Db4	61	4	277.18
D4		62	4	293.66
D#4	Eb4	63	4	311.13
E4		64	4	329.63
F4		65	4	349.23
F#4	Gb4	66	4	369.99
G4		67	4	392.00
G#4	Ab4	68	4	415.30
A4		69	4	440.00
A#4	Bb4	70	4	466.16
B4		71	4	493.88
C5		72	5	523.25
C#5	Db5	73	5	554.37
D5		74	5	587.33
D#5	Eb5	75	5	622.25
E5		76	5	659.26
F5		77	5	698.46
F#5	Gb5	78	5	739.99
G5		79	5	783.99
G#5	Ab5	80	5	830.61
A5		81	5	880.00
A#5	Bb5	82	5	932.33
B5		83	5	987.77
C6		84	6	1046.50	1.05 kHz
C#6	Db6	85	6	1108.73	1.11 kHz
D6		86	6	1174.66	1.17 kHz
D#6	Eb6	87	6	1244.51	1.24 kHz
E6		88	6	1318.51	1.32 kHz
F6		89	6	1396.91	1.40 kHz
F#6	Gb6	90	6	1479.98	1.48 kHz
G6		91	6	1567.98	1.57 kHz
G#6	Ab6	92	6	1661.22	1.66 kHz
A6		93	6	1760.00	1.76 kHz
A#6	Bb6	94	6	1864.66	1.86 kHz
B6		95	6	1975.53	1.98 kHz
C7		96	7	2093.00	2.09 kHz
C#7	Db7	97	7	2217.46	2.22 kHz
D7		98	7	2349.32	2.35 kHz
D#7	Eb7	99	7	2489.02	2.49 kHz
E7		100	7	2637.02	2.64 kHz
F7		101	7	2793.83	2.79 kHz
F#7	Gb7	102	7	2959.96	2.96 kHz
G7		103	7	3135.96	3.14 kHz
G#7	Ab7	104	7	3322.44	3.32 kHz
A7		105	7	3520.00	3.52 kHz
A#7	Bb7	106	7	3729.31	3.73 kHz
B7		107	7	3951.07	3.95 kHz
C8		108	8	4186.01	4.19 kHz
C#8	Db8	109	8	4434.92	4.43 kHz
D8		110	8	4698.64	4.70 kHz
D#8	Eb8	111	8	4978.03	4.98 kHz
E8		112	8	5274.04	5.27 kHz
F8		113	8	5587.65	5.59 kHz
F#8	Gb8	114	8	5919.91	5.92 kHz
G8		115	8	6271.93	6.27 kHz
G#8	Ab8	116	8	6644.88	6.64 kHz
A8		117	8	7040.00	7.04 kHz
A#8	Bb8	118	8	7458.62	7.46 kHz
B8		119	8	7902.13	7.90 kHz
C9		120	9	8372.02	8.37 kHz

Piano range (A0-C8, MIDI 21-108) shown in green. Notes outside standard piano range shown in gray.

How Note Frequencies Are Calculated

The Formula

Hz = 440 x 2^((MIDI - 69) / 12)

Every note is calculated relative to A4 (MIDI 69 = 440 Hz). Each octave doubles the frequency. Each semitone multiplies by the 12th root of 2 (approximately 1.0595).

Example: Middle C (C4)

MIDI number: 60

Steps from A4: 60 - 69 = -9

Ratio: 2^(-9/12) = 0.5946

440 x 0.5946 = 261.63 Hz

This is 12-tone equal temperament (12-TET), the universal standard for Western music tuning.

Frequently Asked Questions

What is the frequency of middle C (C4)? +

Middle C is C4, with a frequency of 261.63 Hz and MIDI number 60. It is the C note closest to the center of a standard 88-key piano and serves as the reference point for the musical octave numbering system.

What frequency is A4? +

A4 is 440 Hz (MIDI 69). This is the international standard tuning pitch defined by ISO 16 in 1955. A4 is the A note above middle C and is the reference pitch used to tune orchestras and instruments worldwide.

What are the 808 bass note frequencies? +

808 bass typically lives in the C1-B2 range: C1 (32.70 Hz), D1 (36.71 Hz), E1 (41.20 Hz), G1 (49.00 Hz), A1 (55.00 Hz), C2 (65.41 Hz), D2 (73.42 Hz), E2 (82.41 Hz), G2 (98.00 Hz), A2 (110.00 Hz), B2 (123.47 Hz). Tune to the root note of your track key.

How do I convert MIDI note numbers to Hz? +

Use the formula: Hz = 440 x 2^((MIDI - 69) / 12). Or use the free Note Frequency Calculator above - enter any note name or MIDI number and get the Hz instantly. You can also go the other direction: enter a Hz value to find the closest note.

Look Up Any Note Instantly

Type any note name (C#4, Bb2, G6) to get the exact Hz. Or enter a frequency to find the closest note. No chart scrolling needed.

Open Note Frequency Calculator

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