IDD or Idd may refer to:

Academia

International Development Department, an academic department on poverty reduction at the University of Birmingham Integrated Dual Degree program

Locations Idd, a parish and former municipality in Halden, Norway

Observances International Dance Day International Day of Democracy

People with the surname

Dolal Idd, an American killed in an exchange of gunfire with Minneapolis police

Science and technology Insulin-dependent diabetes, called diabetes mellitus type 1 Interictal dysphoric disorder International direct dialing, in telephony Iodine deficiency disorders, commonly used when discussing IDD eradication programs IDD, the electric current in the drains of a CMOS circuit Interface Design Description, in the military software standard MIL-STD-498 Intellectual Development Disorder Integration Driven Development