A ChordPro file is a simple text with certain formatting guidelines. It is often used to exchange song sheets between different apps and to publish content on websites. The file format was introduced in 1992 and can have a number of extensions (.cho, .crd, .chopro, .chordpro, .chord, .pro, .cpm, .txt). It allows the formatting of lyrics, chords, chord diagrams and metadata.
ChordPro files are automatically transformed into the Song One format when imported. The chord diagrams of the original document are replaced with a set of diagrams created by Song One in the specified tuning.
ChordPro uses 'directives' to define sections and metadata. Song One converts directives such as 'start_of_verse' and 'start_of_chorus' to labels/tags (e.g. 'Verse', 'Chorus'). Song One's themes are automatically applied to the labeled/tagged sections. (ChordPro directives that specify the font, text sizes or colors are ignored.)