What languages are spoken in Indonesia?

Mainly: Indonesian, English, and Arabic
Indonesian (also called Bahasa Indonesia).
The official language is Indonesian which is standardized Malay
Bahasa Indonesia
Indonesian is the official language, but there are hundreds of smaller languages that are also spoken.
the official language of Indonesia is Bahasa Indonesia
Indonesian
"Bahasa Indonesia" is one of the most-used languages in the world, and derives its roots from ancient Malay/ Malay-Polynesian languages. It has been the official language of Indonesia since 1945. Because it shares its origins Polynesian language, Bahasa Indonesia strongly resembles Bahasa Malayu, which is the official language of Asian neighbor Malaysia. As a widely-used language, Bahasa Indonesia plays an essential role in all modes of communication in the country, such as business, administration, education and media.
There is 1 main language in Indonesia. Bahasa Indonesia is the national language spoken by the Indonesians. However, there are hundreds of regional languages/dialects from all over parts of Indonesia as it is rich of ethnicities and cultures. In addition, there are also many people who speak Dutch and English due to European trade.
Bahasa Indonesia Language. ^^
Indonesian (Bahasa Indonesia) is the official language of Indonesia
Most residents of Indonesian Island speak Indonesian language added with traditional language that depends on the place. For example, the province of Sulawesi-Selatan speaks Indonesian and also Makassarnese, though some people can only speak in Makassarnese (especially elders).
The 1 official language is Indonesian (Bahasa Indonesia). Indonesian is spoken natively by 20% of the population, but almost everyone speaks it as a first or second language.

Javanese and Sundanese are the next most widely used. Javanese has more native speakers than Indonesian.

Indonesian sign languages are not fully standardized, and there are many dialects that are not mutually intelligible with each other. Deaf instruction is usually done in manually encoded Malay, which is not a natural sign language, but rather a code where every sign is used to represent a spoken word.

There are many native languages spoken on the different islands. Here is a complete list of 725 languages spoken in Indonesia:

1. Abinomn
2. Abui
3. Abun
4. Aceh
5. Adang
6. Adonara
7. Aghu
8. Airoran
9. Alor
10. Alune
11. Amahai
12. Amarasi
13. Ambai
14. Ambelau
15. Ampanang
16. Anakalangu
17. Anasi
18. Andio
19. Ansus
20. Anus
21. Aoheng
22. Aputai
23. Aralle-Tabulahan
24. Arandai
25. Arguni
26. As
27. Asilulu
28. Asmat, Casuarina Coast
29. Asmat, Central
30. Asmat, North
31. Asmat, Yaosakor
32. Atohwaim
33. Auye
34. Awbono
35. Awera
36. Awyi
37. Awyu, Asue
38. Awyu, Central
39. Awyu, Edera
40. Awyu, Jair
41. Awyu, North
42. Awyu, South
43. Babar, North
44. Babar, Southeast
45. Bada
46. Badui
47. Bagusa
48. Baham
49. Bahau
50. Bahonsuai
51. Bajau, Indonesian
52. Bakati'
53. Bakati', Rara
54. Bakati', Sara
55. Bakumpai
56. Balaesang
57. Balantak
58. Bali
59. Bambam
60. Banda
61. Banggai
62. Bangka
63. Banjar
64. Bantik
65. Barakai
66. Barapasi
67. Baras
68. Basap
69. Batak Alas-Kluet
70. Batak Angkola
71. Batak Dairi
72. Batak Karo
73. Batak Mandailing
74. Batak Simalungun
75. Batak Toba
76. Bati
77. Batui
78. Batuley
79. Bauzi
80. Bayono
81. Bedoanas
82. Behoa
83. Beneraf
84. Benggoi
85. Benkala Sign Language
86. Bentong
87. Benyadu'
88. Berik
89. Betaf
90. Betawi
91. Biak
92. Bidayuh, Biatah
93. Bidayuh, Bukar-Sadong
94. Biga
95. Bilba
96. Bima
97. Bintauna
98. Biritai
99. Blagar
100. Boano
101. Bobongko
102. Bobot
103. Bolango
104. Bolongan
105. Bonerate
106. Bonggo
107. Budong-Budong
108. Bugis
109. Bukat
110. Bukitan
111. Buli
112. Bunak
113. Bungku
114. Buol
115. Burate
116. Burmeso
117. Buru
118. Burumakok
119. Burusu
120. Buruwai
121. Busami
122. Busoa
123. Campalagian
124. Chinese, Hakka
125. Chinese, Mandarin
126. Chinese, Min Dong
127. Chinese, Min Nan
128. Chinese, Yue
129. Cia-Cia
130. Citak
131. Citak, Tamnim
132. Col
133. Dabe
134. Dai
135. Dakka
136. Damal
137. Damar, East
138. Damar, West
139. Dampelas
140. Dayak
140. Dani, Lower Grand Valley
141. Dani, Mid Grand Valley
142. Dani, Upper Grand Valley
143. Dani, Western
144. Dao
145. Dawera-Daweloor
146. Dela-Oenale
147. Dem
148. Demisa
149. Dengka
150. Dera
151. Dhao
152. Diebroud
153. Dineor
154. Diuwe
155. Dobel
156. Dondo
157. Doutai
158. Duano
159. Duri
160. Duriankere
161. Dusner
162. Dusun Deyah
163. Dusun Malang
164. Dusun Witu
165. Duvle
166. Edopi
167. Eipomek
168. Ekari
169. Elpaputih
170. Elseng
171. Embaloh
172. Emem
173. Emplawas
174. Ende
175. Enggano
176. Enrekang
177. Eritai
178. Erokwanas
179. Fayu
180. Fedan
181. Foau
182. Fordata
183. Galela
184. Gamkonora
185. Gane
186. Gayo
187. Gebe
188. Geser-Gorom
189. Gorap
190. Gorontalo
191. Gresi
192. Haji
193. Hamap
194. Haruku
195. Hatam
196. Helong
197. Hitu
198. Horuru
199. Hoti
200. Hovongan
201. Huaulu
202. Hukumina
203. Hulung
204. Hupla
205. Iau
206. Iban
207. Ibu
208. Iha
209. Iha Based Pidgin
210. Ile Ape
211. Ili'uun
212. Imroing
213. Indonesian
214. Indonesian Sign Language
215. Indonesian, Peranakan
216. Irarutu
217. Iresim
218. Isirawa
219. Itik
220. Iwur
221. Jangkang
222. Javanese
223. Javindo
224. Jofotek-Bromnya
225. Kabola
226. Kaburi
227. Kadai
228. Kafoa
229. Kaibobo
230. Kaidipang
231. Kaili, Da'a
232. Kaili, Ledo
233. Kaili, Unde
234. Kaimbulawa
235. Kais
236. Kaiy
237. Kalabra
238. Kalao
239. Kalumpang
240. Kamang
241. Kamarian
242. Kamaru
243. Kambera
244. Kamberau
245. Kamoro
246. Kangean
247. Kanum, Bädi
248. Kanum, Ngkâlmpw
249. Kanum, Smärky
250. Kanum, Sota
251. Kao
252. Kapauri
253. Kaptiau
254. Karas
255. Karey
256. Karon Dori
257. Kaur
258. Kaure
259. Kauwera
260. Kawe
261. Kayagar
262. Kayan Mahakam
263. Kayan, Busang
264. Kayan, Kayan River
265. Kayan, Mendalam
266. Kayan, Wahau
267. Kayeli
268. Kayupulau
269. Ke'o
270. Kedang
271. Kehu
272. Kei
273. Keijar
274. Kelabit
275. Kelon
276. Kemak
277. Kembayan
278. Kemberano
279. Kembra
280. Kemtuik
281. Kendayan
282. Keninjal
283. Kenyah, Mainstream
284. Kenyah, Wahau
285. Kepo'
286. Kereho
287. Kerinci
288. Ketengban
289. Ketum
290. Kimaghima
291. Kimki
292. Kioko
293. Kirikiri
294. Kisar
295. Koba
296. Kodeoha
297. Kodi
298. Kofei
299. Kohin
300. Kokoda
301. Kola
302. Kombai
303. Komering
304. Komodo
305. Kompane
306. Komyandaret
307. Konda
308. Koneraw
309. Konjo, Coastal
310. Konjo, Highland
311. Kopkaka
312. Koroni
313. Korowai
314. Korupun-Sela
315. Kosare
316. Kowiai
317. Kubu
318. Kui
319. Kula
320. Kulisusu
321. Kumbewaha
322. Kur
323. Kuri
324. Kurudu
325. Kutai
325. Kwer
326. Kwerba
327. Kwerba Mamberamo
328. Kwerisa
329. Kwesten
330. Kwinsu
331. Laba
332. Laha
333. Laiyolo
334. Lamaholot
335. Lamalera
336. Lamatuka
337. Lamboya
338. Lamma
339. Lampung Api
340. Lampung Nyo
341. Larike-Wakasihu
342. Lasalimu
343. Latu
344. Lauje
345. Laura
346. Lawangan
347. Legenyem
348. Lembata, South
349. Lembata, West
350. Lemolang
351. Lengilu
352. Lepki
353. Leti
354. Levuka
355. Lewo Eleng
356. Lewotobi
357. Li'o
358. Liabuku
359. Liana-Seti
360. Liki
361. Lindu
362. Lisabata-Nuniali
363. Lisela
364. Lola
365. Lolak
366. Lole
367. Loloda
368. Loncong
369. Lorang
370. Loun
371. Luang
372. Lubu
373. Luhu
374. Lun Bawang
375. Ma'anyan
376. Ma'ya
377. Maba
378. Maden
379. Madura
380. Mai Brat
381. Mairasi
382. Maiwa
383. Makasar
384. Makian, East
385. Makian, West
386. Maklew
387. Malay
388. Malay, Ambonese
389. Malay, Bacanese
390. Malay, Balinese
391. Malay, Banda
392. Malay, Berau
393. Malay, Bukit
394. Malay, Central
395. Malay, Jambi
396. Malay, Kota Bangun Kutai
397. Malay, Kupang
398. Malay, Larantuka
399. Malay, Makassar
400. Malay, Manado
401. Malay, North Moluccan
402. Malay, Papuan
403. Malay, Tenggarong Kutai
404. Malayic Dayak
405. Malimpung
406. Mamasa
407. Mamboru
408. Mamuju
409. Mandar
410. Mander
411. Mandobo Atas
412. Mandobo Bawah
413. Manem
414. Manggarai
415. Mangole
416. Manikion
417. Manipa
418. Manombai
419. Manusela
420. Mapia
421. Marau
422. Marind
423. Marind, Bian
424. Mariri
425. Masela, Central
426. Masela, East
427. Masela, West
428. Masimasi
429. Masiwang
430. Massep
431. Matbat
432. Mawes
433. Mekwei
434. Mentawai
435. Meoswar
436. Mer
437. Meyah
438. Minangkabau
439. Mlap
440. Mo
441. Modang
442. Modole
443. Moi
444. Moksela
445. Molof
446. Moma
447. Mombum
448. Momina
449. Momuna
450. Mongondow
451. Moni
452. Mor
453. Mor
454. Moraid
455. Mori Atas
456. Mori Bawah
457. Moronene
458. Morori
459. Moskona
460. Mpur
461. Mualang
462. Muna
463. Munggui
464. Murkim
465. Musi
466. Muyu, North
467. Muyu, South
468. Nafri
469. Nage
470. Naka'ela
471. Nakai
472. Nalca
473. Namla
474. Napu
475. Narau
476. Nasal
477. Ndom
478. Nduga
479. Nedebang
480. Ngad'a
481. Ngad'a, Eastern
482. Ngaju
483. Ngalum
484. Nggem
485. Nias
486. Nila
487. Nimboran
488. Ninggerum
489. Nipsan
490. Nisa
491. Nuaulu, North
492. Nuaulu, South
493. Nusa Laut
494. Obokuitai
495. Oirata
496. Okolod
497. Onin
498. Onin Based Pidgin
499. Ormu
500. Orya
501. Osing
502. Ot Danum
503. Padoe
504. Pagu
505. Paku
506. Palu'e
507. Palumata
508. Pamona
509. Panasuan
510. Pancana
511. Pannei
512. Papasena
513. Papuma
514. Patani
515. Paulohi
516. Pekal
517. Pendau
518. Perai
519. Petjo
520. Piru
521. Pom
522. Ponosakan
523. Portuguese
524. Punan Aput
525. Punan Merah
526. Punan Merap
527. Punan Tubu
528. Puragi
529. Putoh
530. Rahambuu
531. Rajong
532. Rampi
533. Rasawa
534. Ratahan
535. Rejang
536. Rembong
537. Retta
538. Riantana
539. Ribun
540. Ringgou
541. Riung
542. Roma
543. Rongga
544. Roon
545. Sa'ban
546. Sabu
547. Sahu
548. Sajau Basap
549. Salas
550. Saleman
551. Saluan
552. Samarokena
553. Sanggau
554. Sangir
555. Saparua
556. Saponi
557. Sarudu
558. Sasak
559. Sauri
560. Sause
561. Sawai
562. Saweru
563. Sawi
564. Sawila
565. Seberuang
566. Sedoa
567. Segai
568. Seget
569. Seit-Kaitetu
570. Sekar
571. Seko Padang
572. Seko Tengah
573. Selaru
574. Selayar
575. Selungai Murut
576. Seluwasan
577. Semandang
578. Sembakung Murut
579. Semimi
580. Sempan
581. Sentani
582. Sepa
583. Serili
584. Serua
585. Serui-Laut
586. Siang
587. Sika
588. Sikaritai
589. Sikule
590. Silimo
591. Simeulue
592. Skou
593. So'a
594. Sobei
595. Sowanda
596. Sowari
597. Suabo
598. Sula
599. Sumbawa
600. Sunda
601. Sunum
602. Suwawa
603. Tabaru
604. Tabla
605. Tae'
606. Tagal Murut
607. Taikat
608. Taje
609. Tajio
610. Talaud
611. Taliabu
612. Taloki
613. Talondo'
614. Talur
615. Tamagario
616. Taman
617. Tanahmerah
618. Tandia
619. Tangko
620. Tarangan, East
621. Tarangan, West
622. Tarpia
623. Tause
624. Tausug
625. Tawoyan
626. Te'un
627. Tebi
628. Tefaro
629. Tehit
630. Tela-Masbuar
631. Teluti
632. Tengger
633. Teor
634. Tereweng
635. Termanu
636. Ternate
637. Ternateño
638. Tetun
639. Tewa
640. Tidong
641. Tidore
642. Tii
643. Toala'
644. Tobati
645. Tobelo
646. Tofanma
647. Tolaki
648. Tomadino
649. Tombelala
650. Tombulu
651. Tomini
652. Tondano
653. Tonsawang
654. Tonsea
655. Tontemboan
656. Topoiyo
657. Toraja-Sa'dan
658. Totoli
659. Towei
660. Trimuris
661. Tsaukambo
662. Tugun
663. Tugutil
664. Tukang Besi North
665. Tukang Besi South
666. Tulehu
667. Tunggare
668. Tunjung
669. Uab Meto
670. Ujir
671. Ulumanda'
672. Uma
673. Uma' Lasan
674. Uma' Lung
675. Una
676. Uruangnirin
677. Usku
678. Viid
679. Vitou
680. Wabo
681. Wae Rana
682. Waigeo
683. Waioli
684. Walak
685. Wambon
686. Wandamen
687. Wanggom
688. Wano
689. Wanukaka
690. Warembori
691. Wares
692. Waris
693. Waritai
694. Warkay-Bipim
695. Waropen
696. Waru
697. Watubela
698. Wauyai
699. Wawonii
700. Wejewa
701. Wemale, North
702. Wemale, South
703. Wersing
704. Woi
705. Wolani
706. Wolio
707. Woria
708. Wotu
709. Yahadian
710. Yalahatan
711. Yale, Kosarek
712. Yali, Angguruk
713. Yali, Ninia
714. Yali, Pass Valley
715. Yamdena
716. Yaqay
717. Yarsun
718. Yaur
719. Yawa
720. Yei
721. Yelmek
722. Yeretuar
723. Yetfa
724. Yoke
725. Zorop
Mainly: Indonesian, English, and Arabic
Indonesian (also called Bahasa Indonesia).