NNI

NNI may refer to:
 * Network-to-network interface, used to interconnect signalling networks in telecommunications
 * Net national income, a term in economics
 * National Nanotechnology Initiative, a U.S. government cross-agency coordinating program
 * Ngagyur Nyingma Institute, a monastic college for Buddhist studies & research
 * Numéro national d'identification, the national identification number used in France
 * Neural Network Intelligence, an open source AutoML toolkit for neural architecture search and hyper-parameter tuning
 * Novo Nordisk Inc., a Danish pharmaceutical company.