It has approximately 32 million native speakers in the western third of Java; they represent about 15% of Indonesia's total population.

[3][4] Sundanese is mainly spoken on the west side of the island of Java, in an area known as Tatar Sunda (Pasundan).

However, Sundanese is also spoken in the western part of Central Java, especially in Brebes and Cilacap Regency, because these areas were previously under the control of the Galuh Kingdom.

Until 1600 AD, Sundanese was the state language in the kingdoms of Salakanagara, Tarumanagara, Sunda, Galuh, Pajajaran, and Sumedang Larang.

During this period, Sundanese was heavily influenced by the Sanskrit language as seen in the Batu Tapak Kaki Kiri Nyoreang inscription at the time of King Purnawarman, using the Pallava script.

Along with transmigration and immigration carried out by the Sundanese ethnics, speakers of this language have spread beyond the island of Java.

For example, in Lampung, South Sumatra, Bengkulu, Riau, West Kalimantan, Southeast Sulawesi, and even outside the country of Indonesia, such as Taiwan, Japan, Australia, and other countries, a significant number of ethnic Sundanese live in areas outside the Pasundan.

Meanwhile, the regional governments of West Java and Banten have been actively promoting the use of Standard Sundanese script (Aksara Sunda Baku) in public places and on road signs.

Other consonants that originally appear in Indonesian loanwords are mostly transferred into native consonants: f/v /f/ → p, sy /ʃ/ → s, z /z/ → j, and kh /x/ → h. Epenthetic semivowels /w/ and /j/ are inserted after a high vowel immediately followed by another vowel, as in the words: Sundanese has an elaborate system of register distinguishing levels of formality.

[10] At the beginning of speech level development, it was known 6 levels of Sundanese language: basa kasar (rough), sedeng (medium), lemes (polite), lemes pisan (very polite), kasar pisan (very rough), and basa panengah (intermediate).

For example, the plural form of the adjective curiga (suspicious) is caruriga and not *caluriga, because the 'r' in the root occurs at the start of the following syllable.

Most active forms of Sundanese verbs are identical to the root, as with diuk "sit" or dahar "eat".

Other words include teu hayang (which can also sound aggressive depending on context) and embung (which is somewhat a casual counterpart of alim).

Sakumna jalma gubrag ka alam dunya téh sipatna merdika jeung boga martabat katut hak-hak anu sarua.

[14] «ساكومنا جالما ڮوبراڮ كا عالم دنيا تَيه سيڤاتنا مَيرديكا جۤڠ بَوڮا مرتبة كاتوت حق۲ أنو سارووا.