Informal Register
Grammar Rule in 30 Seconds
Informal Indonesian is all about efficiency: drop your prefixes, shorten your words, and swap formal pronouns for 'aku' and 'kamu'.
- Drop 'me-' and 'ber-' prefixes from verbs (e.g., 'membeli' becomes 'beli').
- Shorten common words by removing the first syllable (e.g., 'sudah' becomes 'udah').
- Use 'aku/kamu' or 'gue/lu' instead of 'saya/Anda' to show closeness.
Meanings
The informal register in Indonesian, often called 'Bahasa Gaul' or 'Bahasa Sehari-hari', is the variety used in daily conversation, texting, and social media. It prioritizes speed, emotional nuance, and social intimacy over grammatical perfection.
Prefix Deletion
Removing formal prefixes like 'me-', 'ber-', and 'ter-' to make verbs sound more natural and less 'textbook'.
“Kamu lagi baca apa?”
“Dia jalan kaki ke sekolah.”
Word Contraction
Shortening standard words to their final syllables or changing vowels for easier pronunciation.
“Gak apa-apa kok.”
“Kalo gitu, aku pergi dulu.”
Pronoun Shift
Using intimate pronouns to signal a close relationship or a relaxed social setting.
“Aku sayang kamu.”
“Gue gak tau deh.”
Discourse Particles
Adding small words at the end of sentences to convey mood, emphasis, or social pressure.
“Ayo dong!”
“Bagus sih, tapi mahal.”
Prefix Dropping (Formal vs. Informal)
| Formal Verb | Informal Verb | Meaning |
|---|---|---|
| Membaca | Baca | To read |
| Membeli | Beli | To buy |
| Berjalan | Jalan | To walk |
| Berbicara | Ngomong | To speak/talk |
| Melihat | Lihat / Liat | To see |
| Membantu | Bantu / Bantuin | To help |
| Mencari | Cari | To search |
| Mendengar | Dengar / Denger | To hear |
Common Word Contractions
| Formal Word | Informal Form | English |
|---|---|---|
| Tidak | Nggak / Gak | No / Not |
| Sudah | Udah | Already |
| Saja | Aja | Only / Just |
| Kalau | Kalo | If |
| Begitu | Gitu | Like that |
| Begini | Gini | Like this |
| Sebentar | Bentar | A moment |
| Terima kasih | Makasih | Thank you |
Reference Table
| Form | Structure | Example |
|---|---|---|
| Affirmative | Subject + Verb (No Prefix) + Object | Aku beli roti. |
| Negative | Subject + Nggak + Verb | Dia nggak datang. |
| Question | Verb + Gak? / Apa + Verb? | Mau ikut gak? |
| Emphasis | Sentence + Particles (deh/dong/sih) | Bagus deh! |
| Jakarta Slang | Gue/Lu + Verb | Gue tau kok. |
| Short Answer | Udah / Belum / Gak | Udah (Yes, already). |
| Soft Request | Verb + Aja | Tunggu sini aja. |
| Reasoning | Abisnya + Clause | Abisnya dia telat. |
Formalitätsspektrum
Saya sudah makan. (Lunch time)
Aku sudah makan. (Lunch time)
Aku udah makan. (Lunch time)
Gue udah makan nih. (Lunch time)
The Pillars of Bahasa Gaul
Pronouns
- Aku/Kamu I/You (Close)
- Gue/Lu I/You (Jakarta)
Verbs
- Drop me- e.g. Baca
- Drop ber- e.g. Jalan
Particles
- Sih Nuance/Contrast
- Dong Emphasis/Request
Formal vs. Informal Spectrum
Should I use Informal Register?
Is the person older than you?
Is it a professional setting?
Are you friends or peers?
Essential Informal Particles
Emphasis
- • Dong
- • Banget
- • Kok
Nuance
- • Sih
- • Lho
- • Nah
Softening
- • Deh
- • Aja
- • Ya
Examples by Level
Aku mau makan.
I want to eat.
Kamu di mana?
Where are you?
Aku gak tau.
I don't know.
Ini apa ya?
What is this, I wonder?
Aku lagi beli kopi.
I'm buying coffee.
Udah selesai belum?
Is it finished yet?
Bentar ya, aku lagi sibuk.
Wait a sec, I'm busy.
Gak usah repot-repot.
No need to go to any trouble.
Bagus sih, tapi mahal banget.
It's good (admittedly), but really expensive.
Kalo gitu, kita pergi aja.
If that's the case, let's just go.
Gimana sih cara pakenya?
How on earth do you use it?
Boleh pinjem bukunya gak?
Can I borrow the book?
Gue gak nyangka dia bakal telat.
I didn't expect he would be late.
Lu mau ikut nongkrong gak ntar malem?
Do you want to hang out tonight?
Emang bener dia udah nikah?
Is it actually true he's already married?
Jangan gitu dong, kan kita temen.
Don't be like that, we're friends after all.
Bukannya gue pelit, tapi emang lagi bokek nih.
It's not that I'm stingy, it's just that I'm really broke right now.
Lagian dia juga gak bilang dari awal.
Besides, he didn't say anything from the start anyway.
Kok bisa-bisanya kamu lupa bawa kunci?
How on earth could you forget to bring the keys?
Tuh kan, apa gue bilang juga apa!
See! What did I tell you!
Yah, namanya juga usaha, urusan hasil mah belakangan.
Well, that's what effort is like; the results come later (it's a secondary concern).
Gak usah baper lah, dia cuma bercanda doang kok.
Don't be so sensitive (get 'bawa perasaan'), he was just joking.
Abisnya lu kelamaan sih, ya udah gue tinggal.
Because you took too long, well, I just left you behind.
Emangnya situ oke banget sampe berani ngatur-ngatur gue?
Do you think you're so great that you dare to boss me around?
Easily Confused
Learners often use 'nggak' for everything, but 'bukan' is still needed for nouns even in informal speech.
Both are used for emphasis but carry different emotional weights.
Learners might use 'gue' everywhere thinking it's just 'informal'.
Häufige Fehler
Saya mau makan deh.
Aku mau makan deh.
Kamu tidak tahu?
Kamu gak tau?
Anda mau ke mana?
Kamu mau ke mana?
Terima kasih banyak.
Makasih ya.
Aku sedang membaca.
Aku lagi baca.
Dia berjalan ke sini.
Dia jalan ke sini.
Sudah makan belum?
Udah makan belum?
Gue akan pergi.
Gue mau pergi.
Bagus dong, tapi mahal.
Bagus sih, tapi mahal.
Kalo gitu, saya pergi.
Kalo gitu, aku pergi.
Gue gak bisa datang karena ada urusan.
Gue gak bisa datang, soalnya ada urusan.
Sentence Patterns
Aku lagi ___ nih.
Kamu udah ___ belum?
Sebenernya ___ sih, tapi ___.
Gimana kalo kita ___ aja?
Real World Usage
Otw ya, tungguin!
Sesuai aplikasi aja ya Pak.
Eh, lu tau gak si Budi udah resign?
Liburan tipis-tipis dulu deh.
Saya memiliki pengalaman di bidang ini.
Permisi Pak, numpang tanya, jalan ini ke mana ya?
The 'Aja' Rule
Don't 'Gue' Your Boss
Particle Power
Prefixes are for Paper
Smart Tips
Put 'gak' at the end of the sentence instead of using 'Apakah' at the beginning.
Use 'banget' after the adjective instead of 'sangat' before it.
Add 'dong' to the end of your request.
Start your sentence with 'Abisnya' or 'Soalnya' instead of 'Karena'.
Aussprache
Final 'a' to 'e' (Jakarta influence)
In Jakarta slang, many words ending in 'a' are pronounced with a neutral 'e' (schwa), like 'ke mana' becoming 'ke mane'.
Glottal Stop
The 'k' in 'nggak' or 'gak' is usually a glottal stop, not a hard 'k'.
Particle Pitch
Particles like 'dong' and 'deh' usually have a falling pitch to sound friendly.
Request with 'dong'
Beliin dong! (↘)
A friendly, slightly persuasive request.
Memorize It
Mnemonic
Remember 'The 3 S's': Strip the prefixes, Shorten the words, and Swap the pronouns.
Visual Association
Imagine a person taking off a stiff business suit (Formal Indonesian) and putting on a comfortable t-shirt and flip-flops (Informal Indonesian) to hang out at a beach cafe.
Rhyme
Drop the 'me-', keep it free; add a 'deh', sounds okay!
Story
Budi is writing an email to his boss using 'Saya' and 'Membaca'. Then his friend Tono calls, and Budi immediately switches to 'Gue' and 'Baca' because they are going to 'nongkrong' (hang out).
Word Web
Herausforderung
Try to write 3 WhatsApp messages to an imaginary Indonesian friend using at least one shortened word and one particle (e.g., 'deh' or 'dong') in each.
Kulturelle Hinweise
Most informal Indonesian is heavily influenced by the Betawi dialect of Jakarta, which is why 'gue/lu' is so popular.
Indonesians are among the most active social media users. Informal register is the 'official' language of Indonesian Twitter and Instagram.
At a 'Warteg' (street food stall), using informal register shows you are a regular and part of the community.
Informal Indonesian evolved from 'Market Malay' (Melayu Pasar) and was later heavily influenced by the 'Prokem' slang of the 1970s/80s Jakarta youth culture.
Conversation Starters
Lagi ngapain nih?
Udah pernah ke Bali belum?
Menurutmu, film itu bagus gak sih?
Gue lagi bosen nih, ada ide gak?
Journal Prompts
Test Yourself
Aku (sudah) ___ makan tadi.
___ mau pergi ke mana?
Find and fix the mistake:
Saya sedang membaca buku.
Tidak apa-apa.
Match each item on the left with its pair on the right:
A: 'Ayo kita pergi!' B: 'Bentar ___, aku lagi dandan.'
Which of these is informal?
You should use 'gue/lu' when talking to your grandmother.
Score: /8
Ubungsaufgaben
8 exercisesAku (sudah) ___ makan tadi.
___ mau pergi ke mana?
Find and fix the mistake:
Saya sedang membaca buku.
Tidak apa-apa.
1. Saja, 2. Kalau, 3. Begitu
A: 'Ayo kita pergi!' B: 'Bentar ___, aku lagi dandan.'
Which of these is informal?
You should use 'gue/lu' when talking to your grandmother.
Score: /8
FAQ (8)
Not exactly. Slang refers to specific words (like 'bokek' for broke), while 'Bahasa Gaul' refers to the entire informal register, including grammar changes like prefix dropping.
Only if it's a personal email to a close friend. For work or official business, always use formal Indonesian.
The suffix '-in' is the informal version of '-kan' or '-i'. For example, 'membelikan' becomes 'beliin'. It's very common in Jakarta slang.
Yes, but be careful. It can sound very natural if your accent is good, but if used incorrectly, it can sound like you're trying too hard. Start with 'aku/kamu' first.
It doesn't have one meaning! It can mean 'anyway', 'admittedly', or just add a soft emphasis. It's best learned through listening to context.
Yes, because of TV and social media, most young Indonesians understand and use some Jakarta slang, though they may have their own local informal registers too.
Absolutely not. It is a culturally appropriate way of speaking. Knowing when to switch is a sign of high linguistic competence.
If people look at you with a surprised or slightly amused expression when you say 'Saya tidak tahu', you are probably being too formal for the setting.
In Other Languages
Tuteo vs. Usted
Indonesian informal register involves structural simplification (prefix dropping) beyond just pronoun changes.
Tu vs. Vous / Verlan
Indonesian informal register is more widely used in written digital communication than French Argot.
Du vs. Sie / Dialekt
Indonesian drops prefixes; German keeps its complex prefix/suffix system even in slang.
Keigo vs. Plain Form
Japanese uses specific verb endings for politeness; Indonesian uses prefixes.
Fusha vs. Ammiya
Indonesian 'Bahasa Baku' and 'Bahasa Gaul' are still mutually intelligible, whereas some Arabic dialects are not.
Nǐ vs. Nín / Internet Slang
Indonesian informal register is defined by prefix removal, while Chinese has no prefixes to remove.
