D class

D class may refer to:

Ships

 * D-class cruiser (Germany), a pair of proposed cruisers
 * D-class cruiser (United Kingdom), British light cruisers that served during World War II
 * D-class lifeboat, British lifeboats
 * D-class destroyer (disambiguation), several classes of ships
 * British D-class submarine
 * United States D-class submarine
 * D-class ferry, roll-on/roll-off ferries operated by DFDS Seaways

Australia

 * MRWA D class, 2-8-0 type steam locomotives
 * WAGR D class, 4-6-4T tank locomotive
 * WAGR D class (1884), 0-4-0ST tank locomotives
 * WAGR D class (diesel), diesel locomotives
 * D-class Melbourne tram
 * D-class Sydney tram

India

 * DHR D Class, 0-4-0+0-4-0 Garratt-type articulated steam locomotives

New Zealand

 * NZR D class (1874), 33 2-4-0T tank locomotives
 * NZR D class (1929), 1 experimental 0-4-0T locomotives

United Kingdom

 * Metropolitan Railway D Class, tank engines
 * NBR D class 0-6-0T, tank locomotives
 * LNWR Class D, 0-8-0 steam locomotives
 * SECR D class, 4-4-0 tender locomotives

Other uses

 * D-class blimp, United States Navy blimps
 * D-segment, a European vehicle size class
 * In the fictional SCP Foundation, expendable people who are sent on dangerous missions.