Workshop tool · Credits or Premium

Analyse your chord progressions with AI

You have a progression and a question: what key am I in, and where can I go next? Paste your chords and the AI analysis answers with the key, the function of each chord in Roman numerals, three possible continuations and two or three reharmonizations, each one explained and shown as guitar chord diagrams.

1 credit per analysis (5 free when you sign up), unlimited with Premium.

Try it free

Exactly what the AI gives you

You enter 2 to 32 chords in standard notation (C G Am F, Dm7 G7 Cmaj7, F#m7b5…). Optionally, you add a key, a style (pop, rock, jazz, blues, bossa nova, folk, RnB / soul, funk, classical, metal) and an intent ("modulate to G", "jazzier"…). The analysis returns four things:

The detected key, for example "C major" or "A minor", or even a mode such as D Dorian.
A harmonic reading of 2 to 4 sentences, with Roman numeral analysis: C G Am F becomes I-V-vi-IV.
3 suggested continuations, 3 to 6 chords each, with a title and a sentence explaining the choice (cadence, modulation, borrowed chord…).
2 or 3 reharmonizations of your progression, the same length where possible, favouring extensions, tritone substitutions, passing chords, transitional ii-Vs, borrowed chords and slash-chord bass lines.

Every suggestion is displayed with guitar diagrams for its chords.

How to read the analysis: theory in practice

Roman numerals describe a chord's function, not its name. That is what lets you transpose and understand why a progression works.

Dm7 G7 Cmaj7 in C major: ii-V-I, the most played cadence in jazz. The V7 (G7) resolves to I.
Am G F E: i-VII-VI-V in A minor, the Andalusian cadence, which stops on V (a half cadence) and calls you back to Am.
Am F C G is ambiguous: vi-IV-I-V in C major or i-VI-III-VII in A minor. The Key field is there to settle it.

On the reharmonization side, a typical suggestion for C G Am F looks like C, G/B, Am7, Fmaj7: the bass walks down C, B, A and the sevenths soften the sound. Another might slip in an Fm borrowed from C minor, a piece of modal interchange that darkens the return to C. Always play the original and then the suggestion, back to back.

What the AI does not do: the limits

The AI reads chord symbols. It does not listen to your music: there is no audio analysis, and it knows neither your melody nor your vocal line. A reharmonization can therefore clash with a melody note; that is for your ears to catch.

On a short or modal progression, the detected key can be debatable: two chords are not always enough to pin down a key. Enter the key if you know it. And treat every suggestion as an idea to try, not a rule: the AI suggests, you decide with your ears. The workshop's rule-based tools, such as chord substitutions, remain the reference when you want the exact rule behind a chord.

Credits, free and Premium

On a free account, the AI analysis runs on credits:

1 credit per analysis;
5 free credits for every new account, no card needed;
credit packs that never expire: 5 credits for 1.90 €, 25 credits for 6.90 €, 100 credits for 19 €.

With Premium (4.90 € a month or 39 € a year), analysis is unlimited, with no credits needed. Your remaining credits are shown under the input field. Note that re-running a progression from "Recent" starts a new analysis, so it uses a credit on a free account.

How to use it

Paste your chords. Type your progression in the field, chords separated by spaces (Am F C G), or click an example: I-V-vi-IV (pop), ii-V-I (jazz), Rhythm changes, 12-bar blues, Andalusian cadence.
Add context if needed. Open "Options" to set a key, a style and an intent. These fields are optional but they steer the continuations and reharmonizations.
Run the analysis. Click "Analyse". You get the key and the reading in degrees, followed by the "Suggested continuations" and "Reharmonisations & alterations" cards with their diagrams.
Apply and keep going. "Add to my progression" appends a continuation to your chords, "Replace my progression" adopts a reharmonization. "Show on the fretboard" opens the scales that fit your chords, "See substitutions" opens the dedicated tool.

What you can do with it

Getting unstuck while writing

Got a verse in C G Am F and no chorus? Run an analysis with the intent "brighter chorus": the 3 continuations give you three directions to try on the guitar in five minutes.

Understanding a chart you transcribed

You worked out a song's chords but not why they work. The analysis names the key and the function of each chord in the chord progression, and points out the chords that fall outside the scale.

Re-dressing a cover

For a jazz or bossa version of a pop song, pick the style and compare the reharmonizations. Keep the one that serves the melody, then write it into your songbook.

Frequently asked questions

How much does an AI progression analysis cost?

On a free account each analysis costs 1 credit, and every new account gets 5 free credits. After that, packs are available (5 credits for 1.90 €, 25 for 6.90 €, 100 for 19 €, and they never expire). With Premium, analysis is unlimited and needs no credits.

Can the AI get the key wrong?

Yes, especially on a short, ambiguous or modal progression. Am F C G can be read in C major or in A minor. Enter the key in the options if you know it, and always check by ear.

Does the AI analyse audio recordings?

No. It works only from the chord symbols you type. There is no audio analysis and no automatic chord detection from a recording.

How many chords can I analyse?

From 2 to 32 chords per analysis, in standard notation (C, Am, G7, Dm7, F#m7b5, Cmaj9…). A full 12-bar blues fits easily.

Does the AI write solos?

No. The analysis is about harmony: key, degrees, continuations and reharmonizations. To work on improvising over your chords, the solo builder computes scales, arpeggios and target notes.