Indonesia has a total of 17,380 islands.

The province of Papua Barat Daya 1 has the largest number beimg 3,082 while Papua Selatan has 7.

Province	Number of Islands
Indonesia	17,380
Papua Barat Daya1	3,082
Kepulauan Riau	2,028
Sulawesi Tengah	1,600
Papua Barat	1,498
Maluku	1,422
Maluku Utara	975
Nusa Tenggara Timur	653
Sulawesi Tenggara	591
Papua	544
Jawa Timur	538
Kepulauan Bangka Belitung	501
Nusa Tenggara Barat	430
Sulawesi Selatan	394
Sulawesi Utara	382
Aceh	365
Kalimantan Barat	260
Kalimantan Timur	244
Sumatera Utara	228
Sumatera Barat	219
Kalimantan Utara	196
Lampung	172
Kalimantan Selatan	165
Riau	144
Gorontalo	127
DKI Jakarta	113
Banten	80
Jawa Tengah	71
Kalimantan Tengah	71
Sulawesi Barat	69
Papua Tengah	50
Bali	41
DI Yogyakarta	37
Jawa Barat	30
Sumatera Selatan	24
Jambi	14
Bengkulu	9
Papua Selatan	7
Papua Pegunungan	–

Indonesia’s Archipelago: Islands by Province from Largest to Smallest

Indonesia is the world’s largest archipelagic state, stretching thousands of kilometers across Southeast Asia and Oceania between the Indian and Pacific Oceans. While official estimates historically place the total number of islands anywhere between 17,000 and 18,000 (with the Indonesian government and UN bodies tracking official verified counts over time), managing this vast maritime nation requires dividing it into 38 distinct provinces.

The distribution of landmasses, island clusters, and archipelagic regions varies dramatically across these provinces. From monumental islands like Sumatra, Java, and parts of Borneo and New Guinea down to thousands of tiny, uninhabited islets, understanding how Indonesia’s territory is organized provides a fascinating look at its geography.

Indonesia’s Major Island Groups

Before breaking down the provincial layout, Indonesia’s geography is typically categorized into major island groupings and mega-islands:

1. The Greater Sunda Islands: Includes Sumatra, Java, Borneo (Kalimantan), and Sulawesi.
2. The Lesser Sunda Islands: Includes Bali, Lombok, Sumbawa, Flores, Sumba, and Timor.
3. The Maluku Islands (Moluccas): Located between Sulawesi and New Guinea.
4. Western New Guinea: Comprising Indonesia’s easternmost provinces on the island of New Guinea.

Indonesia’s Provinces and Island Distribution

When examining Indonesia’s administrative divisions from largest to smallest—whether by total geographic area or the density of their island groups—the provinces present a diverse mix of mainland sub-regions and dense island archipelagos.

1. The Powerhouse Landmass Provinces (Largest by Area & Major Islands)

Several provinces contain major chunks of Indonesia’s primary mega-islands:

• The Kalimantan Provinces (East, North, South, Central, and West Kalimantan): These provinces make up Indonesia’s portion of Borneo (the third-largest island in the world). While Borneo itself is massive, Kalimantan features numerous river-delta islands and coastal clusters.
• The Western New Guinea Provinces (Papua, West Papua, South Papua, Southwest Papua, Central Papua, and Highland Papua): Encompassing the western half of New Guinea (the world’s second-largest island), these provinces also lay claim to large offshore islands like Yos Sudarso, Biak, and Waigeo.
• The Sumatra Provinces (Aceh, North Sumatra, West Sumatra, Riau, Jambi, Bengkulu, South Sumatra, and Lampung): Sharing the massive island of Sumatra, these regions also govern significant island fringes such as the Mentawai Islands (West Sumatra), Nias (North Sumatra), and Simeulue (Aceh).

2. Dense Island and Archipelago Provinces

Some provinces are uniquely defined by being entirely or primarily composed of island chains:

• Riau Islands Province (Kepulauan Riau): Strategically situated near Singapore and Malaysia, this province is a dense collection of archipelagos, including the Riau Archipelago (Batam, Bintan), the Lingga Islands, the Natuna Islands, and the Anambas Islands.
• Bangka-Belitung Islands Province: Positioned east of Sumatra, this province centers around its two primary large islands—Bangka and Belitung—alongside hundreds of surrounding smaller islets.
• Maluku and North Maluku Provinces: Historically known as the legendary Spice Islands, this region is an intricate web of volcanic and coral islands, including Halmahera, Ceram, Buru, the Aru Islands, and the Tanimbar Islands.

3. Core Population Centers and Smaller Provinces

• The Java Provinces (DKI Jakarta, Banten, West Java, Central Java, DI Yogyakarta, and East Java): Home to the political and economic core of Indonesia on the island of Java (the most populous island on Earth). While Java itself is one unified landmass, provinces like Jakarta and East Java govern famous satellite clusters such as the Thousand Islands (Kepulauan Seribu) and Madura.
• Bali & The Nusa Tenggara Provinces (Bali, West Nusa Tenggara, and East Nusa Tenggara): Stretching east from Java, these provinces govern world-renowned tourist and ecological islands like Bali, Lombok, Sumbawa, Flores, Sumba, and Komodo.
• The Sulawesi Provinces (North, Central, South, Southeast, West Sulawesi, and Gorontalo): Shaped like a giant orchid, Sulawesi features a heavily indented coastline surrounded by major outlier archipelagos like the Banggai, Togian, and Selayar islands.

Indonesian Islands by Size and Province

Island Name	Approximate Area (km2)	Province(s) / Region
New Guinea (Western part)	~421,981 (Indonesian side)	Papua, West Papua, South Papua, etc.
Borneo (Kalimantan region)	~539,460 (Indonesian side)	East, West, South, Central, & North Kalimantan
Sumatra	473,481	Aceh, North Sumatra, Riau, Lampung, etc.
Sulawesi	180,681	Central, South, North, Southeast, & West Sulawesi
Java	138,794	Banten, Jakarta, West/Central/East Java, Yogyakarta
Halmahera	18,040	North Maluku
Seram	17,454	Maluku
Sumbawa	14,386	West Nusa Tenggara
Flores	14,154	East Nusa Tenggara