@tonaljs/roman-numeral

Functions to parse roman numeral strings (like the ones used for chord analysis)

A roman numeral symbol is a string like "bVIImaj7" that can be used to represent chords in an abstract tonality.

Usage

ES6:

import { RomanNumeral } from "tonal";

node:

const { RomanNumeral } = require("tonal");

API

RomanNumeral.get(src: string | Pitch): => RomanNumeral

Get the properties of a roman numeral:

Example:

RomanNumeral.get("bVIIMaj7");
// =>
// {
//   empty: false,
//   name: "bVIIMaj7",
//   roman: "VII",
//   acc: "b",
//   chordType: "Maj7",
//   alt: -1,
//   step: 6,
//   major: true,
//   oct: 0
// }

FAQ

How do I get a roman numeral from an interval

romanNumeral function accepts a Pitch as argument:

import { Interval, RomanNumeral } from "tonal";

RomanNumeral.get(Interval.get("3m")).name; // => "bIII"

Want more?

Take a look to @tonal/progression or @tonal/key