Köchel catalogue

The Köchel catalogue is a catalogue of compositions by Wolfgang Amadeus Mozart, originally created by Ludwig Ritter von Köchel, in which the entries are abbreviated K. or KV. Its numbers reflect the ongoing task of compiling the chronology of Mozart's works, and provide a shorthand reference to the compositions. For example, according to Köchel's counting, Requiem in D minor is the 626th piece Mozart composed, thus is designated K. 626.
Köchel's original catalogue has been revised several times. Catalogue numbers from these revised editions are indicated either by parentheses or by superscript: K. 49 (47d) or K. 47d refers to the work numbered 47d in the sixth edition. The catalog was originally chronological, though revisions made chronological ordering of Mozart's works difficult and as of 2024 a new organizational system is used for the ninth version.

History

In the decades after Mozart's death in 1791 there were several attempts to catalogue his compositions, for example by Franz Gleißner and Johann Anton André, but it was not until 1862 that Ludwig von Köchel succeeded in producing a comprehensive listing. Köchel's 551-page catalogue was titled . Köchel attempted to arrange the works in chronological order, but many compositions written before 1784 could only be estimated, although Leopold Mozart had compiled a partial list of his son's earlier works; Mozart's catalogue of his own compositions allows relatively precise dating of many of his later works. The catalogue included the opening bars of each piece, known as an incipit. Köchel divided the corpus into a main chronology of 626 works, and five appendices, abbreviated Anh. I–V which comprise:

I – Lost authentic works
II – Fragments by Mozart
III – Works by Mozart transcribed by others
IV – Doubtful works
V – Misattributed works

Since Köchel published his original catalogue in 1863, the dating of Mozart's compositions has been subject to constant revision. Many more pieces have since been found, re-dated, re-attributed and re-numbered, requiring three revised editions of the catalogue. Subsequent editions – especially the third edition by Alfred Einstein, and the sixth edition by Franz Giegling,, and – have reflected attempts to arrange the growing list of works in a more accurate chronological order, according to various levels of scholarship. Because of the confusing renumbering between versions, the ninth edition by Neal Zaslaw abandoned the chronological order: all works in the main body of the catalogue that were included in a previous edition return to the oldest number they were given, and works newly included in the ninth edition were given numbers past 626, all the way to 721.
A major shortcoming of K was that there was no room to expand the strictly sequential numbering in the main catalogue to allow for any new discoveries or further reassessment of existing works. For the 1937 edition Einstein reassigned some works from the original K appendices into the main catalogue by interpolating numbers with a lower-case letter suffix. In K some of these were, per intervening scholarship, returned to re-structured appendices:

K. 626a
* K. 626a I – 64 Cadenzas by Mozart to his own keyboard concertos
* K. 626a II – Cadenzas by Mozart to keyboard concertos by other composers
K. 626b – 42 sketches & other fragments by Mozart
Anh. A – Copies by Mozart of other composers' works
Anh. B – Works by Mozart transcribed by others
Anh. C – Doubtful and misattributed vocal and instrumental works

For example, Divertimento for Wind Octet in E was numbered K. Anh. 226 in K; Einstein placed it in the K main catalogue as K. 196e, between K. 196 and K. 197; K reassigned it again to the 'doubtful' appendix C as K. Anh. C 17.01; and K reverts to Einstein's assignment as K. 196e. Some works in Anh. A have been identified since 1965 as by Leopold Mozart. Many works in Anh. C have since been more reliably assigned to other composers, or to Mozart himself.

Edition	Year	Editors	Note
1	1862	Ludwig von Köchel	Original
2	1905		Limited revision: mostly addition of pieces that had since come to light
3	1937	Alfred Einstein
4	1958	Alfred Einstein	Unchanged reprint
5	1961	Alfred Einstein	Unchanged reprint
6	1964
7	1965		Unchanged reprint
8	1983		Unchanged reprint
9	2024	Neal Zaslaw	Chronological ordering abandoned; works no longer renumbered

List of existing Mozart compositions

To maintain as much of the original K-numbering of the list as possible, while re-ordering in the revised, chronological sequence, letters were added to the new numbers. The following list shows the latest edition, Köchel's original designation, and the sixth edition. Other addenda and supplements to the catalogue are marked ''.''

Recordings

Recordings of the complete works of Mozart have been issued three times: on the occasion of the bicentenary of Mozart's death in 1991, Philips Classics Records released a 180-CD collection in 45 box sets and each CD in a jewel case, The Complete Mozart Edition, between 1990 and 1991. A selection of 25 CDs from this set, The Best of the Complete Mozart Edition, was published in 1995. The full selection was then released again in 17 box sets as The Compact Complete Mozart Edition in 2000. The Philips collection was made with recordings from world-renowned artists and is of high audio quality. On the occasion of Mozart's 250th birthday in 2006, Brilliant Classics released a single box with 170 CDs, plus one with liner notes to all works and the libretti to vocal works, Mozart Complete Edition. In 2016, for the 225th anniversary of Mozart's death, Decca Classics and Deutsche Grammophon in partnership with the International Mozarteum Foundation released a box of 200 CDs with 2 hardback books with a new Mozart biography by Cliff Eisen and a newly developed short Köchel guide. Mozart 225: The New Complete Edition contains premiere performances of previously lost compositions and never recorded fragments, as well as key works in alternative versions and recordings of legendary historic performances.