⑨ Transpose a Chord Progression

[Basic Operation]

① Set the key of your chord progression (before conversion) from the dropdown list.

② Enter or copy-and-paste your chord progression text into the text area.

③ Choose the target key from the dropdown list.

* If you choose "Degree names" from the dropdown list, you can convert to degree (Roman numeral) notation.

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[Handy Button Features]

Pressing the " Toggle" button toggles (alternately switches) between the degree-name display and the transposed display.

Pressing the "Transpose +1 more" and "Transpose −1 more" buttons lets you transpose easily in semitone steps.
(Pressing twice transposes by a whole tone, three times by three semitones, and so on.)

* Selecting a new key from the dropdown list resets the effect of these buttons.

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[Comment-Out Feature]

By default, transposition is not applied to the following lines:

• Lines beginning with "//"
• Lines beginning with "※"
• Lines beginning with "【" and ending with "】"
• Lines beginning with "/*" and ending with "*/"

To turn off the comment-out feature, uncheck "Use the default strings" under [Set the Strings for Comment-Out Lines].

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[Set the Strings for Comment-Out Lines]

You can set any string to be used for commenting out, as follows.
* This can be used together with the default settings.

① Check "Use custom strings" under [Set the Strings for Comment-Out Lines].
② Enter any string in the text box that appears.
③ Press the "Add" button.

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[Substitution Using the Alphabet]

* These substitutions only apply when the text can be interpreted as (part of) a chord name. Words that cannot be interpreted as chords (such as English lyrics or notes) are left as they are.

• Entering the lowercase letter "b" replaces it with a "flat (♭)".
• Entering the lowercase "bb" replaces it with a "double flat (𝄫)".
• Entering the lowercase letter "s" replaces it with a "sharp (#)".
• Entering the lowercase "ss", "##", or "x" replaces it with a "double sharp (𝄪)".
• Entering the uppercase letter "I" replaces it with the degree name "Ⅰ".
• Entering the uppercase "II" replaces it with the degree name "Ⅱ".
• Entering the uppercase "III" replaces it with the degree name "Ⅲ".
• Entering the uppercase "IV" replaces it with the degree name "Ⅳ".
• Entering the uppercase "V" replaces it with the degree name "Ⅴ".
• Entering the uppercase "VI" replaces it with the degree name "Ⅵ".
• Entering the uppercase "VII" replaces it with the degree name "Ⅶ".
• Entering the lowercase "i" replaces it with the degree name "Ⅰm".
• Entering the lowercase "ii" replaces it with the degree name "Ⅱm".
• Entering the lowercase "iii" replaces it with the degree name "Ⅲm".
• Entering the lowercase "iv" replaces it with the degree name "Ⅳm".
• Entering the lowercase "v" replaces it with the degree name "Ⅴm".
• Entering the lowercase "vi" replaces it with the degree name "Ⅵm".
• Entering the lowercase "vii" replaces it with the degree name "Ⅶm".

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[Other]

* Symbols such as "-" and "o" are only replaced when they can be interpreted as part of a chord name.

• "-" is nicely replaced with "m".
• "?" and "？" are replaced with "・/・ (repeat sign)".
• "o", "O", "゜", and "〇" are replaced with "dim".
• "φ" and "φ" are replaced with "m7(♭5)".
• "↑" is replaced with "sus".
• "!" is replaced with "omit".
• "^" is replaced with "N.C.".
• "@" is replaced with "blk".

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[Playback Feature]

You can play back the converted chord progression. You can set the BPM, volume, backing pattern, timbre, and more.
* The playback feature is not available while degree names are displayed.

• BPM: Set the playback speed in the range of 40–240.
• Volume: Set it in the range of 0–10.
• Backing pattern: Choose from whole note, quarter notes, eighth notes, sixteenth notes, arpeggio, syncopation, bossa nova style, waltz style, shuffle, and tresillo.
• Pattern speed: Choose from double time, normal, and half time.
• Timbre: Choose from sine wave, square wave, triangle wave, sawtooth wave, electric piano style, and organ style.
• Loop: When turned on, the chord progression plays back on a loop.
• Durations: When turned on, the beat-duration notation is enabled.
• Highlight: The chord currently playing is highlighted.
• Auto-play on transposition: If you press the "Transpose +1 more" or "−1" button during playback, playback automatically restarts from the beginning after transposing.

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[Copy Feature]

Clicking the button at the top right of the converted-text display area copies the converted chord progression to the clipboard.

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[Beat-Duration Notation]

By using special brackets in the chord progression text, you can specify the length of each chord.

• [ ] (square brackets): Plays the chords inside the brackets for half a measure (0.5 measures) each.
  Example: [Gm7-C7] → Gm7 and C7 each last half a measure
• [[ ]] (double square brackets): Plays the chords inside the brackets for 1/4 measure each.
  Example: [[Am-Bm-C-D]] → Each chord lasts 1/4 measure
• {{ }} (curly braces): Plays the chords inside the brackets for 2 measures.
  Example: {{C}} → Plays C for 2 measures

* When you copy the conversion result, the brackets for the duration specification are removed (they are shown as an underline visually).

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[Automatic Conversion of Chord Notation]

During playback, the following chord notations are automatically converted.

• maj7, M7, △7 → Maj7
• m7-5, m7b5 → m7(♭5) (half-diminished)
• dim → dim7
• Maj7(9) → Maj9
• Maj7(+5), Maj7(#5) → augMaj7
• 9♭, 9b → ♭9
• +5 → (#5)

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[MIDI Download]

Pressing the "MIDI" button lets you download the converted chord progression as a MIDI file.
You can import it into a DAW or similar software to use it.

[Notes]

Depending on the key setting and the enharmonic notation, the conversion may not be performed correctly.

Words that cannot be interpreted as chord names (such as section labels or notes) are left unchanged. However, standalone "A"–"G" and "I"–"VII" are still converted as chords/degrees, so we recommend writing sentences as comments (e.g. starting with "//").

There is no text-save feature. Please keep a backup of your original data before using this tool.

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[Intended Uses]

When you want to change the key of an original song or the like, there is no need to rewrite everything by hand.
Just paste the text and set the key.

Sometimes you want to jot down a favorite chord progression using degree names.
Just set the target key to "Degree name notation" and you can convert it easily.

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[Accuracy of Information]

The information provided here may not be accurate.

Of course, we take the greatest care in publishing information and materials.
However, we cannot guarantee the accuracy of the published content.

If you find any incorrect information, we would appreciate it if you could let us know via the contact form.

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[Disclaimer]

We accept no responsibility whatsoever, for any reason, for any damage arising in connection with the use or download of the information and materials published on this site.

Nothing in particular.

Nothing in particular.