About the Chord Finder
This tool builds a chord from a root note and a chord type using standard 12-tone equal-temperament music theory. Every chord is a set of notes stacked at fixed semitone intervals above the root within the 12-note chromatic scale (C, C#, D, D#, E, F, F#, G, G#, A, A#, B). Choose a root and a quality — major, minor, diminished, augmented, a seventh chord, or a suspended chord — and the calculator returns the note names, the interval (scale-degree) formula, and the root note's fundamental frequency in hertz.
How chord formulas work
- Major triad: root, major 3rd (+4 semitones), perfect 5th (+7 semitones) — degrees 1-3-5.
- Minor triad: root, minor 3rd (+3 semitones), perfect 5th (+7 semitones) — degrees 1-♭3-5.
- Diminished triad: root, minor 3rd (+3), diminished 5th (+6) — degrees 1-♭3-♭5.
- Augmented triad: root, major 3rd (+4), augmented 5th (+8) — degrees 1-3-♯5.
- Seventh chords (maj7, dominant 7, m7, m7♭5, dim7) add a fourth note 9-11 semitones above the root, depending on quality.
- Suspended chords (sus2, sus4) replace the 3rd with a major 2nd or perfect 4th, so the chord is neither major nor minor.
Reading the frequency result
The root frequency uses the standard equal-temperament formula f = 440 × 2^((n − 69) / 12), where n is the MIDI note number of the root at the octave you chose and 440 Hz is the international tuning reference for A4 (the A above middle C). Middle C is C4, MIDI note 60, at roughly 261.63 Hz.
Frequently Asked Questions
How are the notes in a chord calculated?
Each chord is built by stacking specific intervals, measured in semitones, above a root note within the 12-tone chromatic scale. A major triad, for example, uses the root, a major third (4 semitones up), and a perfect fifth (7 semitones up).
What is the difference between a major and minor chord?
Both are three-note triads sharing the same root and fifth. The only difference is the third: a major chord uses a major third (4 semitones above the root), while a minor chord uses a minor third (3 semitones above the root), which gives minor chords their darker sound.
Why does a note show as C#/Db instead of one name?
C# and Db are enharmonic equivalents — the same pitch in 12-tone equal temperament with two possible spellings depending on musical key and context. This calculator displays sharp names for simplicity; the pitch itself is identical either way.
What does the root frequency value mean?
It is the root note's fundamental frequency in hertz, calculated with the standard 12-tone equal-temperament formula f = 440 x 2^((n-69)/12), where n is the MIDI note number and A4 (440 Hz) is the tuning reference.
Common Tip Percentages
| Service | Typical Tip Range | Notes |
|---|
| Restaurant (sit-down) | 15–20% | 20%+ for exceptional service |
| Food delivery | 10–20% | Consider extra for long distances |
| Taxi / rideshare | 10–20% | More for assistance with luggage |
| Hotel housekeeping | $2–5/night | Leave daily, not just at checkout |
| Barber / hair salon | 15–20% | On pre-discount total |
| Pizza delivery | 10–15% or $3–5 minimum | Higher in bad weather |
General Household Budget Ratios (50/30/20 Rule)
| Category | % of Net Income | Examples |
|---|
| Needs | 50% | Rent, groceries, utilities, insurance |
| Wants | 30% | Dining out, entertainment, hobbies |
| Savings / Debt | 20% | Emergency fund, retirement, extra payments |
Common Measurement Conversions for Everyday Use
| Quantity | US / Imperial | Metric Equivalent |
|---|
| 1 cup | 8 fl oz | 237 mL |
| 1 pint | 16 fl oz | 473 mL |
| 1 quart | 32 fl oz | 946 mL |
| 1 gallon | 128 fl oz | 3.785 L |
| 1 lb | 16 oz | 453.6 g |
| 1 ft | 12 in | 30.48 cm |