Open A is E2 A2 E3 A3 C#4 E4, low to high. It turns the open strings into an A major chord, but it also raises the D, G, and B strings by a whole step. That tension increase is the part most quick guides understate.
Open the Open A guitar tuner before moving a tuning peg.
Open A tuning notes and frequencies
These targets assume 12-tone equal temperament with A4 set to 440 Hz.
| String | Standard | Open A | Change | Target Hz |
|---|---|---|---|---|
| 6, lowest | E2 | E2 | none | 82.41 |
| 5 | A2 | A2 | none | 110.00 |
| 4 | D3 | E3 | up 2 semitones | 164.81 |
| 3 | G3 | A3 | up 2 semitones | 220.00 |
| 2 | B3 | C#4 | up 2 semitones | 277.18 |
| 1, highest | E4 | E4 | none | 329.63 |
The open chord contains A, C#, and E. The lowest note is E, so the voicing is A major in second inversion rather than a root-position A chord.
How to tune a guitar to Open A without breaking a string
- Tune the unchanged strings first: E2, A2, and E4.
- Raise D3 slowly to E3.
- Raise G3 slowly to A3.
- Raise B3 slowly to C#4.
- Stretch each raised string lightly, then make two more tuning passes.
- Approach every target from below. If a string is sharp, drop under the note and tune upward again.
Do not copy peg direction from a video. Headstock layouts and string winding directions differ; watch the pitch, not the hand motion.
The Open A guitar tension problem
Raising a string by a whole step increases its frequency by about 12.2%. Because tension changes with the square of frequency, the same string at the same scale length gains about 26% tension. Open A does that to three strings at once. The relationship follows the string-tension formula explained by D'Addario.
Our view is blunt: actual Open A is a dedicated-guitar tuning, not the smartest default for a shared acoustic. Use it when you need open strings at the nut for slide, or when the guitar has lighter strings and a setup that tolerates the extra pull.
Stop if a raised string feels abnormally stiff, the bridge lifts, the top deforms, or the neck relief changes sharply. A lighter set can reduce tension, but a technician should assess an older, lightly built, or already stressed instrument.
Open A vs Open G with capo 2
The safer acoustic route is Open G tuning plus a capo at fret 2.
| Method | Strings before capo | Sounding open pitches | Best use |
|---|---|---|---|
| Actual Open A | E A E A C# E | E A E A C# E | Slide at the nut; dedicated electric |
| Open G + capo 2 | D G D G B D | E A E A C# E | Shared acoustic; lower string tension |
The capo method produces the same six sounding pitches, but it shortens the playable scale and removes fret 1 from the working area. That is a much smaller compromise than putting three acoustic strings under 26% more tension.
Open A guitar chords worth learning first
Open A rewards a simple major-chord map:
- Open strings: A major
- Barre all six strings at fret 5: D major
- Barre all six strings at fret 7: E major
- Fret 3 on the C# string only: changes C# to E and removes the major third, useful for an A5 sound
For slide, place the slide directly above the fret wire, not in the middle of the fret. Keep it parallel to the frets and mute behind it with the index finger; otherwise the raised middle strings produce obvious sympathetic noise.
Open A tuning problems
The C# string keeps snapping
The B string is being raised a whole step. Replace an old or kinked string, inspect the nut and saddle for a sharp edge, or use Open G with capo 2. Repeatedly installing another identical string without fixing the contact point is wasted money.
The open chord is right but barred chords sound sour
That is an intonation problem, not a tuning problem. Compare the 12th-fret harmonic with the fretted 12th-fret note and use the guitar intonation check.
The tuner alternates between A and E
Mute the other five strings and pluck once near the bridge. Open tunings create strong sympathetic overtones; a loud, repeated attack gives a microphone tuner more competing information, not less.
FAQ about Open A guitar tuning
Is Open A the same as Open E?
No. Open A is E A E A C# E. Open E is E B E G# B E. Both raise three strings from standard, but they form different major chords.
Can standard guitar strings handle Open A?
Many modern electric sets can, but string condition, gauge, scale length, construction, and setup decide whether it is sensible. On an acoustic, Open G plus capo 2 is the conservative choice.
Do normal chord shapes work in Open A?
No. Standard chord shapes assume E A D G B E. Use the easy straight-barre major chords first, then learn shapes built around the A, C#, and E open strings.
Sources
Using Open G plus capo 2? The Open G tuning songs list includes Open A slide tracks you can play with that setup.
- Fender's Open A sequence confirms the E A E A C# E notes and the three whole-step raises.
- D'Addario String Tension Pro lets you compare a specific gauge, scale length, and tuning instead of guessing.
