7-String Guitar Tuner
Tune a 7-string guitar to standard tuning BEADGBE with a free mic tuner showing note, Hz and cents for all seven strings.
Microphone tuner
Play a string, see exactly how far off it is
- Your browser asks once for the microphone. Choose Allow.
- Audio is analysed on this device. Nothing is recorded or uploaded.
- The screen stays awake while the tuner runs.
Space start or stop 1 to 7 pick a string and hear it Esc stop the tone
| String | Note | Frequency (Hz) |
|---|---|---|
| 7th string (Low B) | B1 | 61.74 |
| 6th string (E) | E2 | 82.41 |
| 5th string (A) | A2 | 110.00 |
| 4th string (D) | D3 | 146.83 |
| 3rd string (G) | G3 | 196.00 |
| 2nd string (B) | B3 | 246.94 |
| 1st string (High E) | E4 | 329.63 |
Values use equal temperament with A4 fixed at 440 Hz. Every frequency links to its own reference page. The tuner above rescales them when you calibrate A4.
A 7-string guitar adds one extra low string below the standard six, tuned a fourth under the low E. That gives you B1, E2, A2, D3, G3, B3 and E4, the standard tuning used on most 7-string instruments in metal and progressive rock.
Tuning the extra low string
The top six strings of a 7-string guitar in standard tuning match a regular 6-string exactly: E2, A2, D3, G3, B3, E4. The seventh string sits a perfect fourth below the low E, landing on B1 at 61.74 Hz, a thick, low pitch that needs a heavier gauge string to stay in tune under normal tension.
Tune the extra string last, after the familiar six are settled, so you have a stable low E as a reference. Because B1 is well below where most guitar tuners are tested, take extra care that the microphone tuner is picking up the fundamental and not a harmonic; playing the string firmly and muting the rest helps.
Frequently asked questions
What is standard tuning for a 7-string guitar?
B1, E2, A2, D3, G3, B3, E4 from the lowest string to the highest. The top six strings match a standard 6-string guitar, with one extra B string added below the low E.
What frequency is the low B string?
B1 is 61.74 Hz in equal temperament with A4 at 440 Hz, noticeably lower than the 82.41 Hz low E of a standard 6-string guitar.
Do I need special strings for a 7-string guitar?
Yes, 7-string sets include a heavier gauge low B string designed to hold proper tension at that pitch. A standard 6-string low E will not sound right tuned down that far.
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Frequencies on this page are computed at build time from twelve tone equal temperament with A4 = 440 Hz, using the twelfth root of two (about 1.059463) per semitone. Nothing is typed in by hand. See the full method and sources. Maintained by FusionStudios. Last reviewed: .