Online Guitar Tuner — Reference Tones & 15 Alternate Tunings
Tune your guitar using reference tones for 15 tunings — including Standard, Drop D, Open G, DADGAD, half-step down, 7-string and baritone. Click any string to hear its exact target pitch and tune by ear. Furthermore, the String Frequencies tab shows the precise Hz for every string in every tuning — adjustable from A4 = 430 Hz (baroque) to 450 Hz. No microphone required.
How to use the Online Guitar Tuner
Select your tuning
Choose from 15 tuning presets: Standard, Drop D, Open G, DADGAD, half step down, 7-string and more. Furthermore, the string buttons update to show the correct note and Hz for each string instantly.
Click a string button to hear its reference tone
Each coloured button corresponds to one guitar string. Furthermore, clicking it plays a sustained reference tone at the exact frequency for that string. Pluck your string and tune it until it matches the tone you hear. The Hz frequency appears on each button for reference.
Tune from below the target pitch
When tuning by ear, always approach the target pitch by tuning upwards. Furthermore, this keeps the string tension pulling in the correct direction and helps the tuning stay stable longer. If your string is above the target pitch, tune it down past the target and then tune up to it.
Adjust the A4 reference pitch if needed
Most instruments use A4 = 440 Hz as the standard concert pitch. Furthermore, the slider allows adjustment from 430 Hz (baroque pitch, used for early music) to 450 Hz (some European orchestras). Adjust this first if you need to match a specific ensemble or instrument.
Check exact frequencies in the String Frequencies tab
Click String Frequencies to see a table of all string notes, their exact Hz values and their wavelengths. Furthermore, this reference is useful for software tuning, acoustic analysis and understanding string relationships.
The 15 guitar tunings and when to use them
Alternate tunings change the pitch of one or more strings to create new chord voicings, resonances and melodic possibilities. Furthermore, many genres have signature tunings that define their sound. The table below summarises the most widely used tunings and their applications.
| Tuning | String notes (6→1) | Best for |
|---|---|---|
| Standard | E A D G B e | All styles — the universal reference tuning |
| Drop D | D A D G B e | Rock, metal — easier power chords on strings 6-4 |
| Half step down | Eb Ab Db Gb Bb eb | Rock — slightly heavier tone, easier bending |
| DADGAD | D A D G A d | Celtic, folk, fingerstyle, Jimmy Page |
| Open G | D G D G B d | Blues, slide, Rolling Stones, fingerstyle |
| Open D | D A D F# A d | Blues slide, folk, Joni Mitchell |
| Drop C | C G C F A d | Modern metal, djent, heavy rock |
| 7-string | B E A D G B e | Extended range, progressive metal, jazz |
How guitar string frequencies are calculated
Guitar string frequencies follow equal temperament — each semitone is a fixed frequency ratio above the previous one. Furthermore, standard tuning places the low E string at MIDI note 40.
Low E (MIDI 40) = 440 × 2^((40−69)/12) = 82.41 Hz
A string (MIDI 45) = 440 × 2^((45−69)/12) = 110.00 Hz
High e (MIDI 64) = 440 × 2^((64−69)/12) = 329.63 Hz
Why tuning up is more stable than tuning down
String tension and elasticity create a slight mechanical difference between tuning from below versus above. Furthermore, tuning down from a sharp pitch leaves the string under slightly less tension and it tends to drift flat. Tuning upwards engages the full string resistance at the target pitch. Moreover, this keeps the tuning more stable during playing.
Worked example: tuning to Open G
Open G (D G D G B d) requires detuning strings 6, 5 and 1 from standard. The process step by step:
| String | Standard | Open G target | Direction | Reference Hz |
|---|---|---|---|---|
| 6 (low) | E (82.41 Hz) | D (73.42 Hz) | Tune DOWN | 73.42 Hz |
| 5 | A (110.00 Hz) | G (98.00 Hz) | Tune DOWN | 98.00 Hz |
| 4 | D (146.83 Hz) | D — no change | Leave | 146.83 Hz |
| 3 | G (196.00 Hz) | G — no change | Leave | 196.00 Hz |
| 2 | B (246.94 Hz) | B — no change | Leave | 246.94 Hz |
| 1 (high) | e (329.63 Hz) | d (293.66 Hz) | Tune DOWN | 293.66 Hz |
What is guitar tuning and why does it matter?
Guitar tuning is the process of adjusting each string's tension to produce the correct target pitch. Furthermore, an out-of-tune guitar sounds wrong in any musical context — even technically perfect playing sounds unpleasant when the fundamental pitches are off. Accurate tuning is the most basic requirement of any guitarist and should be done at the start of every playing session.
Standard tuning (E A D G B e) became dominant because it provides efficient fingering for most chords and scales. Furthermore, the specific intervals between strings allow the same chord shapes to work across most of the neck. Moreover, alternate tunings unlock chord voicings and resonances that standard tuning cannot achieve.
Tuning by ear versus electronic tuners
Tuning by ear using reference tones trains your musical hearing. Furthermore, the ability to hear and correct pitch is a skill that improves all musical contexts. Electronic tuners are faster for gig situations. Moreover, this reference tone approach sits between the two — it uses exact frequencies but develops your ear rather than replacing it.
Why alternate tunings matter
Alternate tunings expand the musical possibilities of the guitar dramatically. Furthermore, Open G tuning makes slide guitar accessible — every open string chord is in tune, and a bottleneck slide can play melodies without fretting. DADGAD produces a suspended, open sound used in Celtic and North African music. Moreover, Drop D tuning allows power chords with a single finger on strings 6, 5 and 4 — a key technique in rock and metal.
Many iconic recordings use alternate tunings. Furthermore, Keith Richards played in Open G for most of the Rolling Stones catalogue. Joni Mitchell used dozens of personal alternate tunings on her albums. Jimmy Page used DADGAD for "Kashmir" and other Zeppelin recordings. Moreover, understanding which tuning a song uses is the first step in learning to play it accurately.
Alternate tunings and capo use
A capo raises all string pitches by a fixed number of semitones — effectively changing the key of any tuning. Furthermore, Open G with a capo at the 2nd fret becomes Open A. DADGAD with a capo at the 2nd fret becomes EBEABE. Moreover, combining alternate tunings with a capo multiplies the sonic possibilities further — many fingerstyle guitarists use specific tuning-and-capo combinations as their signature sound.
Frequently asked questions
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