Online Watermark Databases/Catalogues
- Bernstein - The Memory of Paper(a portal to 42 watermark databases with more than 254,000 watermarks)
- Biteca - Bibliografia de textos catalans antics (filigranes)
- Briquet Online - Repertory Les Filigranes of Charles-Moïse Briquet
- CCF - Corpus Chartarum Fabriano (requires free registration)
- CCI - Corpus Chartarum Italicarum (requires free registration)
- DHWD/DMVA
- Digital Hungarian Watermark Databank
- EEP Watermarks of Early Estonian Prints
- Sammlung Feyerabend Hamburg (watermarks of machine-paper, 20th-21st century)
- FILACAD - Catálogo de filigranas (marcas de agua) de Real Academia de Bellas Artes de San Fernando, Madrid.
- FILHISP - Filigranas Hispánicas
- heridate - dating of papers used for manuscripts, prints and drawings
- LEOcode - Papers of Leonardo da Vinci
- MARCMUS - Music paper and handwriting studies in Portugal
- NGV - Watermarks in the NGV's collection of prints by Albrecht Dürer
- NIKI's - International Database of Watermarks and Paper used for Prints and Drawings (c. 1450-1800)
- Piccard-Online - Watermarks from mainly archive documents (14th-16th century)
- PPO - Printed Piccard Online
- STANSBY - A Digital Catalogue of Watermarks and Type Ornaments Used by William Stansby in the printing of The Workes of Beniamin Jonson
- The WWW Watermark Archive Initiative
- Watermarks in Irish Documents
- WIES - Watermarks in Incunabula Printed in España
- WILC - Watermarks in Incunabula Printed in the Low Countries
- WZIS - Wasserzeicheninformationssystem (Wasserzeichen in den DFG-Handschriftenzentren)
- WZMA - Watermarks of the Middle-Ages (from Austrian depositories, 14th-16th century)