Indonesia is home to over 700 living languages spoken across its extensive archipelago. This significant linguistic variety constitutes approximately 10% of the world’s total languages, positioning Indonesia as the second most linguistically diverse nation globally, following Papua New Guinea. The majority of these languages belong to the Austronesian language family, prevalent in the western and central regions of Indonesia, including languages such as Acehnese, Sundanese, and Buginese. In contrast, the eastern regions, particularly Papua and the Maluku Islands, are home to more than 150 Papuan languages, which are distinct from the Austronesian family and represent a unique linguistic heritage. The language most widely spoken as a native language is Javanese, primarily by the Javanese people in the central and eastern parts of Java Island, as well as across many other islands due to migration.

Languages in Indonesia are classified into nine categories: national language, locally used indigenous languages, regional lingua francas, foreign and additional languages, heritage languages, languages in the religious domain, English as a lingua franca, and sign languages.

National language

The official language of Indonesia is Indonesian (locally known as bahasa Indonesia), a standardised form of Malay, which serves as the lingua franca of the archipelago. According to the 2020 census, over 97% of Indonesians are fluent in Indonesian. The vocabulary of Indonesian borrows heavily from regional languages of Indonesia, such as Javanese, Sundanese and Minangkabau, as well as from Dutch, Sanskrit, Portuguese, Arabic and more recently English. The Indonesian language is primarily used in commerce, administration, education and the media; thus, nearly every Indonesian speaks the language to varying degrees of proficiency. Most Indonesians speak other languages, such as Javanese, as their first language. This makes plurilingualism a norm in Indonesia.

Indigenous languages and regional lingua francas

Indonesia recognizes only a single national language, and indigenous languages are recognized at the regional level, although policies may vary from one region to another. For example, in the Special Region of Yogyakarta, the Javanese language has the status of a regional official language in Yogyakarta under regional law, where it is used for cultural, educational, and communicative purposes, while Indonesian remains the sole national language of administration Javanese is the most spoken indigenous language, with native speakers constituting 31.8% of the total population of Indonesia (as of 2010). Javanese speakers are predominantly located in the central to eastern parts of Java, and there are also sizable numbers in most provinces. The next most widely spoken regional languages in the country are Sundanese, local Malay, Madurese, and Minangkabau. A sense of Indonesian nationhood exists alongside strong regional identities.

There are hundreds of indigenous languages spoken in Indonesia. Most of them are locally used indigenous languages, a category of languages referring to those spoken at the local, regional level, spoken by a small number of people, ranging from a few to a few thousands of people. These include small languages such as Benggoi, Mombum, and Towei. Other languages are spoken at the regional level to connect various ethnicities. For this reason, these languages are known as regional lingua francas (RLFs). According to Subhan Zein, there are at least 43 RLFs in Indonesia, categorized into two types: Malayic RLFs and Non-Malayic RLFs. The former refers to a group of regional lingua francas that are thought of as indigenised varieties of Malay or Indonesian. These include such languages as Ambonese Malay, Banjarese, Manado Malay, and Papuan Malay. The latter refers to regional lingua francas that are not associated with Malay or Indonesian, including Biak, Iban, and Onin.

Foreign languages As early as the seventh century AD, the natives of the archipelago began an intense period of trade with people from China, India and other countries. This was followed by a long period of colonization by the Dutch and Portuguese colonials. The outcome of these processes has been the development of a group of heritage languages spoken by Arab, Chinese, Eurasian and Dutch descendants, among others. Chinese linguistic varieties such as Hokkien, Hakka, and Mandarin are the most common heritage languages. Tamil is also spoken among majority of Indians in the country. A small number of heritage language speakers speak Arabic and Dutch.

Dutch

Despite the Dutch presence in Indonesia for almost 350 years (parts of Indonesia were ruled by the Dutch East India Company and the whole of modern Indonesia was in the Dutch East Indies) the Dutch language has no official status in Indonesia. The small minority that can speak the language fluently are either educated members of the oldest generation, or employed in the legal profession, as certain law codes are still available only in Dutch.

English English has historically been categorized as the first foreign language in Indonesia. However, increasing exposure to English, the decreasing influence of native-speaker norms in the country and the prevalent use of English as a lingua franca in the broader context such as ASEAN means that the categorization has been put into question. Scholars such as Lowenberg argue that English is best seen as an additional language. Meanwhile, Zein argues that English in Indonesia is best categorized as a lingua franca, an argument parallel with Kirkpatrick's contention on the use of English as a lingua franca in the broader ASEAN context.

Other languages Other languages, such as Arabic, Chinese, French, German, Japanese, Korean, Russian, Portuguese and Spanish, are non-native to Indonesia. These languages are included in the educational curriculum and may be categorized as either foreign or additional languages, depending on the instrumental function of the languages, length and types of exposure, as well as the wide-ranging motivations of the speakers or learners who use and or learn them.

Endangered languages

There are 726 languages spoken across the Indonesian archipelago in 2009 (dropped from 742 languages in 2007), the second largest multilingual population in the world after Papua New Guinea. Indonesian Papua, which is adjacent to Papua New Guinea, has the most languages in Indonesia. Based on the Expanded Graded Intergenerational Disruption Scale classification used by Ethnologue (formerly the Summer Institute of Linguistics), 63 languages are dying (shown in red on the bar chart, subdivided into Moribund and Nearly Extinct, or Dormant), which is defined as "The only fluent users (if any) are older than child-bearing age."

Language policy Indonesia's national language policy is governed by various legal frameworks. Article 36C of the 1945 Constitution mandates that matters related to the national flag, language, emblem, and anthem must be regulated by law. This mandate led to the enactment of Law No. 24 of 2009 on the National Flag, Language, Emblem, and Anthem, which dedicates Chapter III (Articles 25–45) to the regulation of the Indonesian language.

In addition to regulating the national language, the government has implemented a Regional Language Revitalization Program (Revitalisasi Bahasa Daerah (RBD)), which aims to preserve and promote local languages by ensuring their transmission to younger generations. To support this initiative, the ministry has published Guidelines for Regional Language Revitalization (Pedoman Model Revitalisasi Bahasa Daerah), providing a structured approach for implementation across different regions.

Indonesia is home to 718 regional languages, many of which are classified as endangered or critically endangered. The revitalization efforts are part of a broader strategy to maintain linguistic diversity while reinforcing the role of Indonesian as the national language.

Languages by speakers

The population numbers given below are of native speakers, excepting the figure for Indonesian, which counts its total speakers. The total population of the country was 237.6 million in 2010. + Largest languages in Indonesia Language Number % of totalpopulation Branch Year surveyed Main areas where spoken Indonesian Malayic 2010 Throughout Indonesia Javanese Javanese 2000 (census) Throughout Java Island and several provinces in Sumatra and Kalimantan islands. Sundanese Sundanese 2016 West Java, Banten, Jakarta Madurese 13,600,000 Madurese 2000 (census) Madura Island (East Java) Minangkabau 5,500,000 Malayic 2007 West Sumatra, Riau, Jambi, Bengkulu, Jakarta Buginese 5,000,000 South Sulawesi 2000 (census) South Sulawesi Palembang Malay 3,900,000 Malayic 2000 (census) South Sumatra Banjarese 3,500,000 Malayic 2000 (census) South Kalimantan, East Kalimantan, Central Kalimantan Acehnese 3,500,000 Chamic 2000 (census) Aceh Balinese 3,300,000 Bali-Sasak-Sumbawa 2000 (census) Bali Island and Lombok Island Betawi 2,700,000 Malay-based creole 1993 Jakarta Sasak 2,100,000 Bali-Sasak-Sumbawa 1989 Lombok Island (West Nusa Tenggara) Batak Toba 2,000,000 Northwest Sumatra–Barrier Islands 1991 North Sumatra, Riau, Riau Islands Ambonese Malay 1,900,000 Malay-based creole 1987 Maluku Makassarese 2,100,000 South Sulawesi 2000 (census) South Sulawesi Min Nan 1,300,000 Sinitic 2000 North Sumatra, Riau, Riau Islands, West Kalimantan Batak Dairi 1,200,000 Northwest Sumatra–Barrier Islands 1991 North Sumatra Batak Simalungun 1,200,000 Northwest Sumatra–Barrier Islands 2000 (census) North Sumatra Batak Mandailing 1,100,000 Northwest Sumatra–Barrier Islands 2000 (census) North Sumatra Jambi Malay 1,000,000 Malayic 2000 (census) Jambi Gorontalo 1,000,000 Philippine 2000 (census) Gorontalo Ngaju Dayak 900,000 West Barito 2003 Central Kalimantan Nias 800,000 Northwest Sumatra–Barrier Islands 2000 (census) Nias Island, North Sumatra Batak Angkola 700,000 Northwest Sumatra–Barrier Islands 1991 North Sumatra Manado Malay 800,000 Malay-based creole 2001 North Sulawesi North Moluccan Malay 700,000 Malay-based creole 2001 North Maluku Hakka 600,000 Sinitic 1982 Bangka Belitung, Riau Islands and West Kalimantan Batak Karo 600,000 Northwest Sumatra–Barrier Islands 1991 North Sumatra Uab Meto 600,000 Timor-Babar 1997 West Timor (East Nusa Tenggara) Bima 500,000 Bima 1989 Sumbawa Island (West Nusa Tenggara) Manggarai 500,000 Sumba-Flores 1989 Flores Island (East Nusa Tenggara) Toraja-Sa’dan 500,000 South Sulawesi 1990 South Sulawesi, West Sulawesi Komering 500,000 Lampungic 2000 (census) South Sumatra Tetum 400,000 Timor-Babar 2004 West Timor (East Nusa Tenggara) Rejang 400,000 Land Dayak 2000 (census) Bengkulu Muna 300,000 Muna–Buton 1989 Southeast Sulawesi Sumbawa 300,000 Bali-Sasak-Sumbawa 1989 Sumbawa Island (West Nusa Tenggara) Bangka Malay 300,000 Malayic 2000 (census) Bangka Island (Bangka Belitung) Osing 300,000 Javanese 2000 (census) East Java Gayo 300,000 Northwest Sumatra–Barrier Islands 2000 (census) Aceh Cantonese 300,000 Sinitic (Yue) 2000 North Sumatra, Riau Islands, Jakarta Tolaki 300,000 Celebic 1991 Southeast Sulawesi Taeʼ 300,000 South Sulawesi 1992 South Sulawesi

Languages by family Several prominent languages spoken in Indonesia sorted by language family are:

Austronesian languages – (Malayo-Polynesian branch). Most languages spoken in Indonesia belong to this family, which in return are related to languages spoken in Madagascar, Malaysia, Philippines, New Zealand, Hawaii and various Oceanian countries. Javanese language, spoken in Yogyakarta, Central Java and East Java. Speakers are also found in Lampung since Javanese migrants make up more than half of the province's population. Also found throughout Indonesia and by migrants in Suriname. Most populous Austronesian language by number of first language speakers.