ALTERNATE TUNINGS / SIX-STRING GUITAR
Drop C guitar tuner
Drop C is C G C F A D (CGCFAD), from the thickest string to the thinnest. Select a string, then use your microphone or hear its reference tone.
Ready when you are
Waiting for a note
Audio stays on your device.
No recording. No upload.
Pluck one string. Keep the others muted.
Hold a steady note, then confirm and move to the next string.
FROM E A D G B E
How to tune to Drop C
Lower E2 to C2 by four semitones (two whole steps). Lower each of the other five strings by two semitones (one whole step).
Check every string change ↓- 01
Start with the lowest string
Select string 6, C2. Remove any capo and play the open string. Enable microphone, allow access and keep the other strings quiet. The target is 65.41 Hz; the octave number matters.
- 02
Adjust, then let the note settle
From standard tuning, lower the pitch toward the target. Once close, use small adjustments: raise a flat note or lower a sharp one. Pluck gently again and wait for “Stable and in tune” before pressing “Confirm & next string”.
- 03
Finish the six-string check
Retune all five remaining strings using the changes below. After all six are confirmed, the tool returns to low C for a final check. Confirm that reading to finish the pass.
STRING 6 → STRING 1
Drop C notes & Hz
CGCFAD means C G C F A D, low to high. String 6 is the thickest; string 1 is the thinnest. The numbers in C2 and C3 identify different octaves, not string numbers.
Calculated in twelve-tone equal temperament at A4 = 440 Hz, rounded to two decimals.
| String | Standard → target | Change | Hz |
|---|---|---|---|
| 6 · low | E2 → C2 | Down 4 semitones | 65.41 |
| 5 | A2 → G2 | Down 2 semitones | 98.00 |
| 4 | D3 → C3 | Down 2 semitones | 130.81 |
| 3 | G3 → F3 | Down 2 semitones | 174.61 |
| 2 | B3 → A3 | Down 2 semitones | 220.00 |
| 1 · high | E4 → D4 | Down 2 semitones | 293.66 |
REFERENCE SOUND
Tune to Drop C without a microphone
Select a string in the tuner, then press Hear reference. It plays a three-second tone for that string. Listen, let it finish, and compare your open string by ear. Repeat for each target in the table. You do not need microphone permission for reference playback.
Reference playback turns microphone detection off. It cannot check your instrument or complete the confirmation steps for you. Enable the microphone again if you want a measured reading; avoid playing the reference into the microphone.
If you are already in D standard (D G C F A D), lower only string 6 from D2 to C2. If you are in Drop D, lower all six strings by a whole step to reach Drop C.
Choose a string & hear its note ↑SAME LOW NOTE, DIFFERENT TUNING
Drop C vs C standard
C standard is C F B♭ E♭ G C. Drop C is C G C F A D. They share the lowest note, but the other five strings are different. Dropping only the low E to C while leaving A D G B E unchanged does not produce the CGCFAD preset on this page.
| Tuning | Notes | What changes? |
|---|---|---|
| Drop C | C G C F A D | This page: low C with G–C–F–A–D above it. |
| C standard | C F B♭ E♭ G C | Every string is four semitones below E standard. |
| D standard | D G C F A D | Only the sixth string differs from Drop C. |
Drop C is also one whole step below Drop D on every string. Use the Drop D tuner for that separate preset.
WHEN THE READING ISN’T CLEAR
Drop C tuning help
Can I use this for acoustic or electric guitar?
The six target notes are the same for both. The microphone needs a clean, audible single string: mute the other strings and avoid distortion or effects. An unplugged electric guitar may be too quiet for a built-in microphone. Use reference tones if the input cannot hear it reliably. Real-instrument and physical mobile-device validation is still pending.
Why do my strings feel loose or buzz in Drop C?
Lowering all six strings reduces their tension. A tuner can show pitch but cannot fix fret buzz, string feel or intonation. If you plan to keep this tuning, string gauge and guitar setup may need attention. There is no single gauge recommendation for every scale length and playing style.
Why does it show an octave mismatch or strong harmonics?
Low C2 and C3 share a note name but are an octave apart. A plucked string also produces higher harmonics that can dominate the input. Check the selected string, mute the others and pluck again gently. Do not tighten the string by an octave to chase the display. The tool rejects some ambiguous readings, but cannot distinguish every possible harmonic-only signal.
What if the microphone does not work on my phone?
Open the page in your browser, allow microphone access in that site’s permissions and check that your input is not being used by another app. Return to this tab and press Enable microphone again after an interruption. If permission is blocked or the input is too quiet, use the reference-tone method. Physical iPhone and Android testing remains outstanding.
Is this a bass or seven-string tuner?
No. These targets are for six-string guitar. Matching a note letter alone is not enough: a bass may need a different octave, outside the intended range. This tool does not provide bass, seven-string or custom presets.
What does “in tune” mean here?
A stable reading must stay within ±3 cents of the selected target for the confirmation hold. That is a software rule, not a measured accuracy guarantee. Read the detection method, test coverage and limits.
Note layouts and tuning changes checked against Fender’s Drop C guide and Gibson’s Drop C notes. Frequencies are calculated; tuning comparisons use semitone transposition from E standard. Updated October 25, 2026.