A Java library used to read and write vCard data streams as defined in RFC2426. Currently supports vCard 3.0 but is stated to be under active development.
Java parser library
ez-vcard is a java parser library for vCard. It supports all versions of the vCard standard (2.1, 3.0, 4.0) as well as xCard, hCard, and jCard.
Milton is a java library for WebDAV, CalDAV and CardDAV server implementations.
The library used by CalendarServer as part of its CardDAV/vCard support.
Python CardDAV client and library
pyCardDAV is a CLI CardDAV client (for use with mutt etc.) and also contains a reusable CardDAV module.
Open Source Command-Line Tool
vdirsyncer is a command-line tool to synchronize a CalDAV/CardDAV server with a local iCalendar/vCard file, or a folder of those. It can also be used to synchronize two DAV servers with each other.
The library used by the Mulberry client for its vCard handling.
Not supported since 2005
A Python library used to read and write vCard data streams as defined in RFC2426. Also does iCalendar.
Not supported since 2009
vCard4j is a Java library used to read and write vCard data streams as defined in RFC2426.
Not supported since 2003