Guitar Tuning Chart: Standard & Alternate Tunings

Guitar tuning is defined by the fundamental vibrational frequency of each open string. While standard tuning ($E_2$–$A_2$–$D_3$–$G_3$–$B_3$–$E_4$) accommodates the majority of popular guitar literature, alternate tunings alter interval relationships across strings to enable open-chord drones, extended chord voicings, or slackened string tension for aggressive heavy-metal riffs.

The mathematical frequency of any note in 12-tone equal temperament (12-TET) referenced to $A_4 = 440\text{ Hz}$ is determined by:

$$f = 440 \times 2^{\frac{m - 69}{12}}$$

where $m$ represents the note’s integer MIDI number ($C_4 = 60$, $A_4 = 69$). Below are the exact frequencies, note designations, and MIDI note values for every tuning shipped in our browser tuner.

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1. Standard 6-String Guitar Tuning

Standard guitar tuning spans two octaves between the lowest and highest open strings, arranged in ascending perfect fourths with a single major third interval between strings 3 and 2 ($G_3$ to $B_3$).

String	Note Name	Scientific Pitch	Frequency (Hz)	MIDI Number	Interval from Next String
6 (Lowest)	E	$E_2$	82.41	40	Perfect 4th
5	A	$A_2$	110.00	45	Perfect 4th
4	D	$D_3$	146.83	50	Perfect 4th
3	G	$G_3$	196.00	55	Major 3rd
2	B	$B_3$	246.94	59	Perfect 4th
1 (Highest)	E	$E_4$	329.63	64	—

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2. Drop Tunings (Drop D & Drop C)

Drop tunings lower only the lowest string (or lower the entire instrument and drop the lowest string an additional whole step). This creates a root-fifth-octave power chord across the lowest three strings that can be fretted with a single finger.

Drop D Tuning ($D_2$–$A_2$–$D_3$–$G_3$–$B_3$–$E_4$)

Only string 6 is detuned down one whole step from $E_2$ (82.41 Hz) to $D_2$ (73.42 Hz). Strings 5 through 1 remain identical to standard tuning.

String	Note Name	Frequency (Hz)	MIDI Number	Change from Standard
6	D	73.42	38	Down 2 semitones (-200 cents)
5	A	110.00	45	None
4	D	146.83	50	None
3	G	196.00	55	None
2	B	246.94	59	None
1	E	329.63	64	None

Drop C Tuning ($C_2$–$G_2$–$C_3$–$F_3$–$A_3$–$D_4$)

Every string is detuned one whole step below standard tuning ($D$ standard), and the 6th string is dropped an additional whole step to $C_2$ (65.41 Hz).

String	Note Name	Frequency (Hz)	MIDI Number	Pitch Relation
6	C	65.41	36	4 semitones below $E_2$
5	G	98.00	43	2 semitones below $A_2$
4	C	130.81	48	2 semitones below $D_3$
3	F	174.61	53	2 semitones below $G_3$
2	A	220.00	57	2 semitones below $B_3$
1	D	293.66	62	2 semitones below $E_4$

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3. Half Step Down / E-Flat Tuning ($E\flat_2$–$A\flat_2$–$D\flat_3$–$G\flat_3$–$B\flat_3$–$E\flat_4$)

Popularized by Jimi Hendrix, Stevie Ray Vaughan, and heavy rock ensembles, tuning down one half step (100 cents) across all six strings reduces string tension, darkens overall acoustic resonance, and makes bending heavy strings easier.

String	Enharmonic Pitch	Frequency (Hz)	MIDI Number	Semitone Shift
6	$E\flat_2$ / $D\sharp_2$	77.78	39	-100 cents
5	$A\flat_2$ / $G\sharp_2$	103.83	44	-100 cents
4	$D\flat_3$ / $C\sharp_3$	138.59	49	-100 cents
3	$G\flat_3$ / $F\sharp_3$	185.00	54	-100 cents
2	$B\flat_3$ / $A\sharp_3$	233.08	58	-100 cents
1	$E\flat_4$ / $D\sharp_4$	311.13	63	-100 cents

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4. Open Tunings (Open G & Open D)

Open tunings configure the open strings to form a major triad when strummed without fretting. Widely used for bottleneck slide guitar, blues, and folk fingerpicking.

Open G Tuning ($D_2$–$G_2$–$D_3$–$G_3$–$B_3$–$D_4$)

Open G produces a clean G major chord ($G$–$B$–$D$). Strings 6, 5, and 1 are detuned down one whole step; strings 4, 3, and 2 remain unchanged.

String	Note	Frequency (Hz)	MIDI Number	Chord Function
6	D	73.42	38	5th ($D$)
5	G	98.00	43	Root ($G$)
4	D	146.83	50	5th ($D$)
3	G	196.00	55	Root ($G$)
2	B	246.94	59	Major 3rd ($B$)
1	D	293.66	62	5th ($D$)

Open D Tuning ($D_2$–$A_2$–$D_3$–$F\sharp_3$–$A_3$–$D_4$)

Open D produces a full D major chord ($D$–$F\sharp$–$A$). String 3 is lowered one half step to the major third ($F\sharp_3$); strings 6, 2, and 1 are lowered one whole step.

String	Note	Frequency (Hz)	MIDI Number	Chord Function
6	D	73.42	38	Root ($D$)
5	A	110.00	45	5th ($A$)
4	D	146.83	50	Root ($D$)
3	$F\sharp$	185.00	54	Major 3rd ($F\sharp$)
2	A	220.00	57	5th ($A$)
1	D	293.66	62	Root ($D$)

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5. DADGAD Celtic Modal Tuning ($D_2$–$A_2$–$D_3$–$G_3$–$A_3$–$D_4$)

DADGAD (often called Celtic tuning) avoids a defined major or minor third, forming a suspended fourth modal chord ($D\text{sus4}$). It allows rich drone accompaniment behind fiddle tunes and modal acoustic fingerstyle compositions.

String	Note	Frequency (Hz)	MIDI Number	Role in Dsus4
6	D	73.42	38	Root ($D_2$)
5	A	110.00	45	5th ($A_2$)
4	D	146.83	50	Octave Root ($D_3$)
3	G	196.00	55	Suspended 4th ($G_3$)
2	A	220.00	57	5th ($A_3$)
1	D	293.66	62	High Root ($D_4$)

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6. Extended Range: 7-String, 8-String & Baritone Guitars

Extended-range guitars descend deep into bass registers, demanding careful intonation and pickup adjustment.

Instrument / Tuning	String	Note	Frequency (Hz)	MIDI Number
7-String Standard	7 (Lowest)	$B_1$	61.74	35
	6–1	$E_2$ to $E_4$	82.41 to 329.63	Standard 6-String
8-String Standard	8 (Lowest)	$F\sharp_1$	46.25	30
	7	$B_1$	61.74	35
	6–1	$E_2$ to $E_4$	82.41 to 329.63	Standard 6-String
Baritone Guitar (B Standard)	6	$B_1$	61.74	35
	5	$E_2$	82.41	40
	4	$A_2$	110.00	45
	3	$D_3$	146.83	50
	2	$F\sharp_3$	185.00	54
	1	$B_3$	246.94	59

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7. 12-String Guitar Course Pairings

A 12-string guitar features six courses. Courses 6 through 3 are octave pairs, consisting of a standard pitch primary string and a lighter string tuned one octave higher ($+12$ semitones). Courses 2 and 1 are unison pairs, tuned to the exact same frequency.

Course	Primary String (Note / Hz / MIDI)	Secondary String (Note / Hz / MIDI)	Pairing Type
6	$E_2$ · 82.41 Hz (MIDI 40)	$E_3$ · 164.81 Hz (MIDI 52)	Octave (+12 semitones)
5	$A_2$ · 110.00 Hz (MIDI 45)	$A_3$ · 220.00 Hz (MIDI 57)	Octave (+12 semitones)
4	$D_3$ · 146.83 Hz (MIDI 50)	$D_4$ · 293.66 Hz (MIDI 62)	Octave (+12 semitones)
3	$G_3$ · 196.00 Hz (MIDI 55)	$G_4$ · 392.00 Hz (MIDI 67)	Octave (+12 semitones)
2	$B_3$ · 246.94 Hz (MIDI 59)	$B_3$ · 246.94 Hz (MIDI 59)	Unison (Identical pitch)
1	$E_4$ · 329.63 Hz (MIDI 64)	$E_4$ · 329.63 Hz (MIDI 64)	Unison (Identical pitch)

To tune any of these configurations interactively using your device microphone, visit our browser-native Guitar Tuner. Once the six open-string names are stable, the guitar fretboard notes guide extends them to every fret from 0 to 12, with a full neck diagram and a two-week memorisation plan.