Indonesia NIK Validator
Validate the structure of an Indonesian NIK (KTP number): real province code, embedded birth date (day +40 for women) and serial, decoded locally in your browser. Includes batch checking with CSV export.
This is a structure check (province code, birth date, serial). NIK has no public check digit — only Dukcapil can confirm a NIK is registered, and nothing you type here leaves your browser.
Check an Indonesian NIK
The 16-digit NIK on every KTP encodes where the card was first issued (province, regency, district), the holder's birth date — with 40 added to the day for women — and a 4-digit serial. This tool decodes those fields and flags impossible values, entirely in your browser.
Every Indonesian KTP carries a 16-digit NIK (Nomor Induk Kependudukan) with a fixed anatomy: two digits each for the province, regency/city and district where it was first issued, six digits of birth date in DDMMYY order, and a four-digit serial starting at 0001. For women, 40 is added to the birth day — someone born on the 5th shows 45. The NIK stays the same for life, even if the holder moves.
Unlike Brazil's CPF or Poland's PESEL, the NIK has no public check digit, so no algorithm can bless a number as genuine. What a structure check can catch is impossible values: a province code that does not exist (valid codes run from 11 Aceh to 96 Papua Barat Daya, including the four provinces created in 2022), a birth day of 32, a month of 13, or a 0000 serial. This tool decodes and flags exactly those, entirely in your browser.
Registry truth lives only with Dukcapil: whether a NIK is issued, active and matches a name can only be confirmed there. Treat this page as a fast pre-check for form validation and list cleaning — the batch panel and the cross-country batch ID workbench handle whole columns with per-row reasons and CSV export.
FAQ
What do the 16 digits of a NIK mean?
Positions 1–6 are the region of first issuance (2 digits each for province, regency/city, district), positions 7–12 are the birth date as DDMMYY, and positions 13–16 are a serial that starts at 0001 for people sharing the same region and birth date.
Why does the birth day look too big?
For women, 40 is added to the day. A NIK showing 450497 in positions 7–12 belongs to a woman born on 5 April 1997; a man born the same day would show 050497. Days 01–31 mean male, 41–71 mean female.
Is there a check digit like CPF or PESEL?
No — the NIK has no public checksum. This tool verifies structure and semantics (real province code, real calendar date, non-zero serial). Only Dukcapil, the population registry, can confirm a NIK is actually issued and active.
Which province codes are valid?
BPS codes from 11 (Aceh) to 96: the classic 34 provinces plus the four created in the 2022 Papua split — Papua Selatan (93), Papua Tengah (94), Papua Pegunungan (95) and Papua Barat Daya (96). Code 3201… means Kabupaten Bogor in Jawa Barat (32), for example.
Does the NIK change when someone moves?
No. The region digits reflect where the NIK was first issued and never change afterwards — so decoding a NIK tells you where the person was registered, not where they live today.
Is my list uploaded anywhere?
No. Decoding, validation, batch checks and CSV export all run locally in your browser.