Musicalion is a subscription-based online library offering over 58,000 compositions, including both public-domain and self-published works. Over 39,000 of the compositions are available in MusicXML format. Compositions are available in a mix of PDF, MusicXML, MIDI, and original source formats. An annual subscription is €29.
This site offers downloads of over 1 million score files in MuseScore, MusicXML, PDF, MIDI, and MP3 formats. Public domain scores can be downloaded free of charge. Downloading copyrighted scores requires a Musescore PRO subscription for $49/year.
IMSLP Petrucci Music Library
IMSLP, the International Music Score Library Project, has one of the largest collection of online public domain scores in the Petrucci Music Library, with over 180,000 works. IMSLP provides files in PDF format, but an increasing number of these PDF files include MusicXML attachments.
Choral Public Domain Library
The library has over 39,000 choral and vocal public domain scores available. An increasing number are available directly in MusicXML format. Many others are available in source file formats (Finale, Sibelius, capella, Myriad, etc.) that can be exported to MusicXML files.
Werner Icking Music Archive
This site has many free sheet music files. While many are in PDF format only, an increasing number are in MusicXML format or MusicXML-compatible source formats like Finale and capella. The Archive has since merged with IMSLP, but this original site is still available online.
OpenScore is a project to create interactive scores of the world’s public domain sheet music, free to use for any purpose. It is the first project of its kind funded by a Kickstarter campaign. Downloads are available in MuseScore, MusicXML, PDF, MIDI, MP3, and Braille formats.
The Josquin Research Project
This open-access site allows users to search, browse, and analyze complete scores of polyphonic music from roughly 1420 to 1520. The project started to support comparative analysis of the works attributed to the composer Josquin des Prez. It then expanded to support a larger range of musicological questions about Renaissance music and now includes over 700 works.
This site includes a large selection of hymn tunes available in MusicXML, PDF, and MIDI formats.
The Band Music of Amilcare Ponchielli
An online critical edition of the band music of this Italian composer best known for his operas. The editions have been created by Prof. Henry Howey at Sam Houston State University from autograph manuscripts found in the Biblioteca statale in Cremona, Italy. The music is available in MusicXML, PDF, and MP3 formats.
The Full English Transcription Programme at Folkopedia
The Folkopedia wiki is dedicated to the Folk Arts of England and beyond. The Full English Transcription Programme available on Folkopedia is transcribing the online manuscript collection of The Full English Digital Archive into notation files in MusicXML, PDF, and MIDI formats.
NEUMA is a digital library that aims at publishing on-line rare corpora of music. Currently their collection focuses on French music from the late 17th through the early 19th centuries. NEUMA is part of the French Huma-Num digital humanities project. Music is available in MusicXML, PDF, and PNG formats.
SymbTr – Turkish Makam Music Symbolic Data Collection
This data collection was developed to support the computational analysis of Turkish Makam music. The version 2.0 release contains 2,200 pieces. Downloads are available in MusicXML, mu2, MIDI, PDF, and text formats.
Visaudio Designs provides designs for marching bands and percussion ensembles, including both ready-made and custom shows. The shows include editable notation files in both MusicXML and Sibelius formats.
YourScore Music offers downloadable, customizable music for young instrumental groups, designed to address individual learning in an ensemble setting. Purchases include both MusicXML and PDF files, with the MusicXML intended for customizing the arrangement to the needs of the ensemble.
La mà de guido
A music publishing house that specializes in music by Spanish and Catalan composers. They sell music as MusicXML files, as well as PDF files and print publications.
Lusthof der Muziek (in Dutch)
The Garden of Musical Delights offers public domain music from Flanders and the Netherlands. The focus is on traditional music, folk music, songbooks, broadsides, dance music, and music of anonymous composers. MusicXML is one of the formats available for download.
Folkoteca Galega (in Galician)
Offers Galician music in MusicXML, PDF, and MIDI formats.
Project Gutenberg Sheet Music Project
Has over 30 public domain scores available for free download in MusicXML format, including the Beethoven string quartets.
New Hymns for Worship
Dave Marney’s site offer hymns composed by Marney and friends for free download as MusicXML files.
Hausmusik (in German)
This site offers free scores in a variety of formats, including MusicXML format.
SEILS (Symbolically Encoded Il Lauro Secco) Dataset
A dataset of 30 madrigals for five unaccompanied voices from the 16th century anthology of Italian madrigals Il Lauro Secco.
Jingju Music Scores Collection
A collection of 92 jingju musical scores, gathered for the analysis of jingju (also known as Beijing or Peking Opera) singing. The collection is available for research purposes from the contact address on the web site.
This site sells Christian worship music in a variety of score and audio formats, including full orchestral Finale files. Their SongMap technology allows you to make custom arrangements of both the score and audio files.
Oliver Seely’s (mostly) Clarinet Page
Offers over 150 clarinet and woodwind scores available in Finale format, including chamber music and concertos.