The Constitution of India says: The official language of the Union shall be Hindi in Devanagari script.
The form of numerals to be used for the official purposes of the Union shall be the international form of Indian numerals.Being the official script for Hindi, Devanagari is officially used in the Union Government of India as well as several Indian states where Hindi is an official language, Bihar, Chhattisgarh, Haryana, Himachal Pradesh, Jharkhand, Madhya Pradesh, Mizoram, Rajasthan, Uttar Pradesh and Uttarakhand, and the Indian union territories of Delhi, Andaman and Nicobar Islands and Dadra and Nagar Haveli and Daman and Diu.
[2] Gujarat[3][4] and West Bengal also officially use Devanagari, as these two states recognise Hindi as an additional official language.
[5] The Devanagari script (देवनागरी, romanized: Devanāgarī) is the officially mandated script of the Bodo language in Assam,[6] the Konkani language in Goa,[7] and Sanskrit in Himachal Pradesh.
[8] The Gurmukhi script (Punjabi: ਗੁਰਮੁਖੀ) is the official script for the Punjabi language in Punjab,[9] and Delhi.