Databases

#ALCHEMISTIC MANUSCRIPTURES - Database of alchemical manuscripts (Adam McLean)
AUTOGRAPHS - Database of medieval German autographs and originals (University of Münster)
#BIBLIOTHECAHAGIOGRAPHICA LATINA MANUSCRIPTA - Database of manuscripts with hagiographic content used by the Bollandists (Société des Bollandistes)
Manuscripta juridica: Index of manuscripts on Roman and canon law. Database version (Max Planck Institute for European Legal History)
Donne e cultura scritta del Medioevo - Database for the search for manuscripts by female scribes (English version also available) (Uni Cassino)
Union Catalogue of Manuscripts from the Islamic World - database for manuscripts in Arabic script in England (partly with object description)
HSA - Manuscript Archive of the Berlin-Brandenburg Academy of Sciences and Humanities - Descriptions of medieval German-language manuscripts (BBAW Berlin)
JORDANUS - Database of medieval scientific manuscripts (BADW Munich)
KRISTELLER, Paul Oscar: Latin manuscript books before 1600. A list of the printed catalogues and unpublished inventories of extant collections. 5th ed. Munich 2003 (#MGH-Bibliothek)
Llull-DB - Ramon Llull Database with a list of manuscripts containing works by Llull (Uni Barcelona)
Handschriftencensus - Marburg Census of German-language manuscripts of the Middle Ages
MEDIEVAL LOGICAL MANUSCRIPTS - Database on medieval manuscripts on logic (L.M. de Rijk, E.P. Bos) #http://mlm.huygensinstituut.nl:3000/ not available 01/2023
Logicalia Medievalia - Latin logical manuscripts before 1220 - project page with further thematic links (University of Venice)
Münster manuscripts - reconstruction of the holdings destroyed in World War II using documents from the HSA (BBAW Berlin, link broken 01/2023) - cf. also under Münster (Overgauw)
OPAC of Portuguese church libraries, partly with old holdings (mainly prints) #http://catalogo.cesareia.com/ - no longer available 01/2023
PhiloBiblon - database on manuscripts from Castile, Galicia, Portugal and Spain (University of Berkeley)
REPERTORIUM CHRONICARUM - Database with possibility to browse medieval chronicle manuscripts (Mississippi State University)
SCHOENBERG DATABASE - Database of manuscripts and fragments traded at auctions (University of Pennsylvania (Philadelphia), beta version 2016)
Seymour de Ricci Bibliotheca Britannica Manuscripta Digitized Archive - a searchable database containing the digitized notes of the historian and bibliographer Seymour Montefiore Robert Rosso de Ricci (1881-1942) made for the compilation of his unfinished Bibliotheca Britannica Manuscripta

More collections

Country-specific offers can also be found on the overview pages for the respective country
Overview of sales catalogs containing medieval manuscripts. #https://bibliologiemedievale.wordpress.com/catalogues/ - Page no longer active 01/2023
Link collection (as of 2009!) - Further links via the Virtual Library History (University of Munich)