Knowing the notes on the neck is what lets you find a chord root, move a scale to a new key or read a chord chart without counting frets one by one. This finder lays out every note, string by string and fret by fret, up to the 24th fret. On a laptop the neck runs across the screen like the guitar in your lap; on a phone it runs down the screen so the frets stay big enough to tap.
Tap any spot to hear it on a real guitar sound and see its name, its octave, its pitch in hertz, and every other place on the neck where the very same pitch lives. That last part is the secret of the fretboard: the note at the 5th fret of the 6th string is the open 5th string, and most notes appear two or three times within the first twelve frets.
Choose “One note” and pick C to see every C on the neck at once, or keep all notes showing and highlight one. “Naturals” hides the sharps and flats so the seven natural notes stand out, which is the best way to start. Names can be sharps (C♯), flats (D♭) or both. Switch to “Hidden” to test yourself: every spot is blank until you tap it.
Any tuning works: standard, drop D and the other drop tunings, open G, D, E and C, DADGAD, lowered tunings, 7- and 8-string guitar, 4-, 5- and 6-string bass, ukulele, mandolin, tenor banjo, or your own (type the notes lowest string first). Left-handed players can flip the neck in Display settings. Save the chart as a picture or print it.