Devanagari ( /ˌdeɪvəˈnɑːɡəriː/; Hindustani: [d̪eːʋˈnaːɡri]; देवनागरी Devanāgarī — compound of "deva" (देव) and "nāgarī" (नागरी) ), also called Nagari (Nāgarī, नागरी, the name of its parent writing system), is an abugida alphabet of India and Nepal. It is written from left to right, does not have distinct letter cases, and is recognizable (along with most other North Indic scripts, with few exceptions like Gujarati and Oriya) by a horizontal line that runs along the top of full letters. Devanāgarī is the main script used to write Standard Hindi, Marathi, and Nepali. Since the 19th century, it has been the most commonly used script for Sanskrit. Devanāgarī is also employed for Bhojpuri, Gujari, Pahari, (Garhwali and Kumaoni), Konkani, Magahi, Maithili, Marwari, Bhili, Newari, Santhali, Tharu, and sometimes Sindhi, Dogri, Sherpa and by Kashmiri-speaking Hindus. It was formerly used to write Gujarati.

Devanāgarī is part of the Brahmic family of scripts of India, Nepal, Tibet, and South-East Asia. It is a descendant of the Gupta script, along with Siddham and Sharada. Eastern variants of Gupta called Nāgarī are first attested from the 8th century CE; from c. 1200 CE these gradually replaced Siddham, which survived as a vehicle for Tantric Buddhism in East Asia, and Sharada, which remained in parallel use in Kashmir. An early version of Devanagari is visible in the Kutila inscription of Bareilly dated to Vikram Samvat 1049 (i.e. 992 CE), which demonstrates the emergence of the horizontal bar to group letters belonging to a word.