Standard tuning: the six strings
A six-string guitar is tuned, from the thickest string to the thinnest, to E - A - D - G - B - E. The numbering runs the opposite way from what you might expect: string 6 is the lowest (the thickest one, on top when you hold the guitar) and string 1 is the highest.
The number after each letter (E2, A2…) is the octave. It keeps the two E strings apart, since they sound two octaves from each other. The frequencies are approximate, rounded to two decimals and based on A = 440 Hz.
| String | Note | Notation | Frequency (Hz) |
|---|---|---|---|
| 6th (lowest) | E | E2 | 82.41 |
| 5th | A | A2 | 110.00 |
| 4th | D | D3 | 146.83 |
| 3rd | G | G3 | 196.00 |
| 2nd | B | B3 | 246.94 |
| 1st (highest) | E | E4 | 329.63 |
Classical, acoustic and electric guitars share the same tuning. The string material and tension change, but the notes are the same.
How to use the microphone tuner
The ABC SyG Guitar Tuner listens through the microphone on your phone or computer, detects the note you play and shows with a needle whether you're flat, sharp or in tune. The audio is analyzed on your own device.
- Leave the instrument set to "Guitar (6 strings)" and tap «Turn on the microphone». Your browser asks for permission the first time: accept it.
- Play an open string (no finger on the fretboard) with medium force and let it ring. One string at a time.
- Watch the needle. On the left, the string is flat and you need to tune up (tighten it); on the right, it is sharp and you need to tune down.
- Turn the tuning peg slowly until «In tune!» appears and the needle rests in the center. Then move to the next string.
- When you finish all six, check the first string again: changing the tension of the others moves the neck slightly, and the first one is usually a little off.
If you don't know which note belongs to a string, tap the string name on the screen ("Open strings") to hear the reference note: it helps you tune by ear by comparing. You can also change the frequency of A (440 Hz by default) and choose whether notes are shown as letters (C D E…) or as Do Re Mi.
How much error is acceptable: cents
The distance between two notes is measured in cents. One semitone (for example E to F, or one fret to the next) is 100 cents. A difference of about 5 cents is very hard to hear, even for a trained ear, so there is no need to chase perfection while the needle trembles.
Once you are off by 10 or 15 cents, though, it becomes audible, especially in chords: two strings that are slightly apart produce a wobbling beat that gives the mistuning away.
Always tune up to the note
If a string is sharp, don't stop on the note: lower it a bit past the target and then come back up until the needle centers. There are two reasons. The first is mechanical: the gear in the tuning peg has a little slack, and if you approach the note by raising the tension, that slack is taken up and the string holds better. The second is that strings tend to loosen over time rather than tighten, so a string that was just lowered is more likely to drift flat.
With new strings the problem multiplies: they stretch during the first hours of playing and the guitar goes out of tune every few minutes. That's normal. Tune, gently stretch each string by pulling it up from the middle of the neck, and tune again; repeat two or three times. Within a couple of days they settle.
Tuning without a tuner: the fifth-fret method
This is the classic backup when your battery dies or you have no microphone. You need one string tuned correctly as a starting point, for example the 6th against a reference (a tuning fork, a piano or the reference sound in the tool). Then:
- Press a finger on the 5th fret of the 6th string: it sounds an A. It must match the open 5th string. Adjust the 5th.
- 5th fret of the 5th string: D. Match it to the open 4th.
- 5th fret of the 4th string: G. Match it to the open 3rd.
- 4th fret of the 3rd string (here it's the 4th, not the 5th): B. Match it to the open 2nd.
- 5th fret of the 2nd string: E. Match it to the open 1st.
The method has one flaw: any error is carried from string to string. It makes the guitar sound consistent with itself, but it doesn't guarantee absolute pitch. Confirm with a tuner when you can.
Alternate tunings
Many songs use a tuning other than standard. The most common ones come from moving one or more strings:
| Tuning | 6th to 1st string | What changes |
|---|---|---|
| Standard | E2 A2 D3 G3 B3 E4 | Reference |
| Half step down | Eb Ab Db Gb Bb Eb | All six strings drop one semitone |
| Drop D | D2 A2 D3 G3 B3 E4 | Only the 6th drops a whole tone: E to D |
| DADGAD | D2 A2 D3 G3 A3 D4 | The 6th drops, the 2nd goes B to A and the 1st goes E to D |
| Open G | D2 G2 D3 G3 B3 D4 | Strumming the open strings sounds a G major chord |
The guitar tuner only lists standard tuning as its open strings. For any of the alternatives, use the "Chromatic (any note)" mode: it tells you the nearest note to what you play and you adjust until it matches the one in the table. In half step down, for example, the 6th string has to land on D sharp or E flat.
Bass, ukulele and violin
The tuners for other instruments work the same way: pick the instrument, turn on the microphone and go string by string.
| Instrument | Strings (lowest to highest) | Frequencies (Hz) |
|---|---|---|
| 4-string bass | E1 A1 D2 G2 | 41.20 / 55.00 / 73.42 / 98.00 |
| Ukulele (standard tuning) | G4 C4 E4 A4 | 392.00 / 261.63 / 329.63 / 440.00 |
| Violin | G3 D4 A4 E5 | 196.00 / 293.66 / 440.00 / 659.26 |
A bass sounds an octave lower than the four lowest strings of a guitar. In the usual ukulele tuning the 4th string (G) is higher than the 3rd (C): this is called re-entrant tuning. With a low-G ukulele, use the chromatic tuner. On a violin, use the small fine tuners on the tailpiece for small corrections, not the big pegs.
Common problems and how to fix them
- The tuner shows nothing or jumps between notes: there is probably background noise, or you are playing two strings at once. Turn off the TV, bring the guitar closer to the microphone and mute the neighboring strings with your hand.
- A string goes out of tune right away: it may be a new string that hasn't stretched, a loose tuning peg (tighten its screw if it has one) or a string badly wound on the post.
- Each open string is in tune, but chords sound off: this is an intonation problem. Compare the open-string note with the same string at the 12th fret; if the difference is clear, the guitar needs a setup (old strings, string height or saddle position).
- A string buzzes: that usually comes from a fret, string height or a loose screw, not from the tuning.
- You play very hard and the tuner reads sharp at first: a hard pluck makes the string sound slightly sharp at the start before it settles. Let the sound stabilize before reading the needle.
Frequently asked questions
What is standard guitar tuning?
From the 6th to the 1st string: E, A, D, G, B, E (E2 A2 D3 G3 B3 E4). It is the tuning used by most songs, books and tutorials.
Can you tune a guitar with your phone?
Yes. The ABC SyG Guitar Tuner uses the microphone of your phone or computer. Play one open string at a time, with little background noise, and follow the needle until it says «In tune!».
Why does my guitar go out of tune so fast?
The most common cause is new strings, which stretch during the first days, or changes in temperature and humidity. It can also be a loose tuning peg or a badly wound string.
Do you tune from the thick string to the thin one or the other way around?
The usual order is from the 6th (thickest) to the 1st. What matters is checking the first string again at the end, because the neck moves with the tension of the others.
Does the same tuner work for electric, acoustic and classical guitars?
Yes: all three share the same tuning. An unplugged electric is quiet, so hold it close to the microphone and play a bit harder.