| Harmonic | Frequency | Note | Fret | Cents |
|---|
Enter a guitar string's fundamental frequency—either by selecting a standard tuning (E2 through E4) or entering a custom frequency in Hz. The calculator multiplies the fundamental by each harmonic number (1–16) to find the frequency of each harmonic. Each frequency is converted to its nearest equal-temperament note and compared to that note's "perfect" frequency to calculate the cents deviation. Fret positions show where you can touch the string to emphasize each harmonic.
A harmonic is a frequency that's an integer multiple of the fundamental. A note (like C4 or A3) is a specific pitch in the chromatic scale. Most harmonics align closely with standard notes, but not perfectly—that's why the 7th harmonic sounds "out of tune."
The 7th harmonic has a frequency ratio of 7:1 with the fundamental. In just intonation (pure ratios), this creates a pitch about 31 cents flat compared to equal temperament's tempered intervals. This is a mathematical consequence of how whole-number ratios relate to the 12-tone chromatic scale.
Touch the string lightly (don't press down) at the fret position listed in the "Fret" column, then pluck near the bridge. The string will vibrate in segments, amplifying that harmonic. The 12th fret (octave) and 7th fret (harmonic 3) are easiest for most players.
Yes. The "Custom Frequency" field accepts any value in Hz. This is useful if your string is tuned lower or higher than standard (e.g., a dropped tuning or a capo effect), or if you want to analyze harmonics for any frequency source.
Cents measure how far a harmonic drifts from equal temperament. A trained ear can detect deviations over ±10 cents. High deviations (like the 7th harmonic's −31 cents) explain why some harmonics sound slightly out of tune compared to the chromatic scale.
Real strings aren't perfectly flexible, so they have slight stiffness that causes higher harmonics to be slightly sharper than ideal. This effect grows stronger with thicker strings and shorter lengths. It's why acoustic guitars sound richer but less "perfect" than synthesizers.
Estimate only. Results reflect your inputs and standard formulas. Double-check important decisions independently.