Chord Calculator

A chord is a root plus a recipe of intervals. Choose the root note and the quality — major, minor, a seventh, a suspension — and this calculator spells the chord exactly: every note it contains, in order, ready for piano, guitar or staff paper.

Chords Are Interval Recipes

Strip the mystique and a chord quality is a list of semitone distances from a root: the major triad is 0, 4, 7 (root, major third, perfect fifth); the minor triad lowers the third by one semitone to 0, 3, 7 — the smallest edit in music, and the whole difference between the two emotional poles of Western harmony. Every quality in the calculator is such a list: the dominant seventh adds 10 to the major recipe, the diminished triad stacks minor thirds (0, 3, 6), the augmented stacks major thirds (0, 4, 8), and the suspensions replace the third outright (sus4 puts 5 where 4 or 3 would go — a third withheld, which is why suspended chords feel unresolved by design). Learn the ten recipes on this page and you hold the spelling of every common chord in every key: the calculator is the recipes made instant, transposition included, because adding a root's offset to a fixed list is all transposing ever was.

Worked Example: C Major, and One Semitone of Melancholy

The defaults spell the first chord every musician meets: root C (offset 0) plus the major recipe gives C · E · G. Now flip only the quality to minor and watch the recipe's middle number fall from 4 to 3: the output becomes C · Eb · G (spelled C# style as D# by the calculator's sharp convention — the note in the widget flags exactly this etiquette). One semitone in one voice converts the anthem into the lament, a disproportion between cause and effect that harmony teachers have marvelled at for centuries. Sevenths enrich the demonstration: C dominant 7 reads C · E · G · A# (Bb) — the recipe 0, 4, 7, 10 — whose tension against the home key powers the blues, while C major 7 (0, 4, 7, 11) keeps the same skeleton and swaps the tension for a shimmer. The calculator's lists make these family relations visible at a glance, which is the fastest harmony education ever devised: recipes, compared.

Why Spelling Is Etiquette, Not Sound

The widget's note carries a real doctrine: in equal temperament, C# and Db are the same piano key, and the calculator's sharp spellings will occasionally offend a flat key's notation (an Eb major chord appearing as D# major's notes). Formal spelling follows the key signature and the rule that each letter name appears once per scale — F major's fourth is Bb, never A#, though the pitch is identical. Instruments do not care; readers of notation do, because letter-consistent spelling makes patterns visible (a triad stacks in thirds: C-E-G, D-F-A — every chord on this page is letter-thirds when spelled by the book). Treat the calculator as the pitch authority and your key signature as the spelling authority, and the two will never quarrel: it gives you the sounds, in the order the recipe demands; etiquette dresses them for the page.

The Circle of Fifths Is a Recipe Map

Arrange the twelve roots by ascending fifths (C, G, D, A, E, B, F#, C#…) and every recipe on this page draws a pattern: the major chords of neighbouring keys share two of their three notes, which is why songs modulate to the fifth so smoothly — the recipe lists overlap almost entirely across the border. The circle also explains the calculator's spelling etiquette in full: keys accumulate sharps (or flats) one per fifth-step, so the "correct" spelling of a chord's third is decided by how far around the circle the key lives. Guitarists meet the geometry as the CAGED system — five shapes tiling the neck — which is the circle of fifths folded onto six strings. One page computes the chords; this paragraph names the map they all live on, and a musician who holds both — recipes and map — can find any chord, in any key, from first principles, forever.

Power Chords: The Recipe with the Third Removed

Rock's foundational sonority is a recipe edit this page makes legible: the power chord is root and fifth only (0, 7), the third deleted entirely — which is why it sounds neither major nor minor and why it survives the distortion that turns richer chords to mud (a distorted third generates intermodulation products that fight the harmony; the bare fifth, a near-perfect ratio, stays clean). A generation of guitarists learned music theory backwards from that fact: first the two-note shape that works everywhere, then the curiosity about what the missing number was. The calculator spells the full recipes; the power chord is the standing reminder that subtraction is also composition — and that the interval list, read critically, tells you not only what a chord contains but what it can afford to lose.

Related Tools

More from the Other Calculators hub: the Fret Calculator for where these chords live on a guitar neck, and the Harmonic Series Calculator — the overtone ladder that makes thirds and fifths sound like home.

Frequently Asked Questions

What is the difference between a chord and a scale?

A scale is a key's full vocabulary (typically seven notes, the reservoir); a chord is a word spoken from it (typically three or four notes, sounded together or in quick succession). The recipes here are stated in semitones, independent of any scale — which is why a C major chord can appear in the keys of C, G and F alike, borrowing its notes from each reservoir in turn. Songwriting craft is largely the diplomacy between the two levels: chords chosen from the scale behave (diatonic harmony), chords imported from outside it thrill (borrowed chords, secondary dominants) — and this calculator spells the imports as faithfully as the natives, since intervals answer to no key.

Why does the minor chord sound sad?

Culture and acoustics share the blame in proportions nobody has settled: the minor third's frequency ratio (6:5) is slightly more complex than the major third's (5:4), sitting further from the harmonic series' simplest agreements, and a millennium of Western music has paired the mode with laments until the association trained itself. What the calculator contributes to the debate is the startling smallness of the difference — one semitone in one voice, 4 becoming 3 in the recipe — against the vastness of the emotional effect, a leverage ratio that should humble anyone who thinks musical meaning lives in big gestures. It lives, demonstrably, in single semitones.

What are inversions?

The same recipe with a different note in the bass: C major in first inversion is E · G · C (the third at the bottom), in second inversion G · C · E. Inversions change a chord's stability and voice-leading without touching its identity — figured-bass shorthand has catalogued them since the Baroque — and pianists and guitarists think in them constantly, since the "shape" under the fingers is usually an inversion, not the root-position stack the calculator prints. Spell the chord here, then put any of its notes lowest: that is the whole of inversion theory, and the recipe list is exactly the set of legal bass notes.

What do add9, 13 and other extensions add?

More recipe entries, stacked in thirds above the seventh: a 9 is the second scale degree an octave up (add 14 semitones' worth of interval class 2 to the list), an 11 the fourth, a 13 the sixth. Cadd9 is the major recipe plus 2: C · E · G · D — a major triad with a colour note and no seventh, hence "add" rather than the full extension stack. The calculator's ten qualities cover the working core; extensions are the same grammar with longer lists, and a reader who has internalised the interval-recipe idea can extend any of these by hand — which is the understanding this page is really selling, with the spellings as its free samples.

How do I play these on guitar?

Find the notes on the fretboard (the hub's Fret Calculator places the positions), and take the standard open shapes as your starting dialect: C major's open shape sounds C · E · G · C · E — the recipe's notes, doubled and inverted by the tuning's convenience. Guitar chord boxes are recipes filtered through six strings in fourths: some notes double, some inversions are forced, and the instrument's genius is that transposition is a capo or a barre away — the recipe unchanged, the whole hand shifted. The calculator spells what the shape must contain; the fretboard decides how your fingers vote on the arrangement.

Which chord quality should a beginner learn first?

Major and minor triads, because the entire popular repertoire is a conversation between those two recipes; then the dominant seventh, whose tension-and-release is the engine of blues, jazz and most choruses' final turns. The calculator's order is a syllabus in disguise: triads, sevenths, suspensions, the symmetrical diminished and augmented (each divides the octave evenly — 3s and 4s respectively — which is why they sound unmoored and why film scores reach for them). Ten recipes, honestly learned with their interval lists, outlast a thousand memorised chord diagrams, because diagrams are per-instrument and recipes are forever.