Roman Numeral Converter

Convert chord progressions into Roman numerals (I, IV, V, vi) in any key. Useful for songwriting, Nashville numbers, and music theory.

Key

Mode

Show Nashville Numbers (1, 4, 5, 6m)

Input Paste chords (commas, spaces, or new lines)

Output Ready

Notes: This converter reads the chord root (and the root of slash chords like D/F#). It keeps your chord qualities as a suffix after the numeral (example: V7, ii7, Imaj7).

How it works

The tool maps each chord’s root note to a scale degree (1–7) in the selected key, then displays the corresponding Roman numeral. In major mode, the default diatonic qualities are I, ii, iii, IV, V, vi, vii°.

FAQ

Does it support slash chords?

Yes. It uses the chord root (left side) and ignores the bass note after the slash for the numeral.

Can I use this for Nashville numbers?

Yes — Roman numerals and Nashville numbers are closely related. This is great for analyzing progressions quickly.

Need to change keys too?

Use the Chord Transposer to move a full chart into a new key.