How is a CCCD number structured?

The 12 digits are a 3-digit province code, a 1-digit gender-and-century code, the 2-digit birth year, and a 6-digit serial. The 4th digit gives gender (even male, odd female) and the century — 0/1 for the 1900s, 2/3 for the 2000s, 4/5 for the 2100s, and so on.

How do the gender and century share one digit?

The 4th digit pairs them. Divide by two for the century (0 → 1900s, 1 → 2000s, 2 → 2100s); even is male and odd is female. So digit 0 means a man born in the 1900s, digit 3 means a woman born in the 2000s.

How does the tool find the full birth year?

It adds the century start to the two-digit year in positions 5–6. For example digit 0 fixes the 1900s, and a year value of 99 gives 1900 + 99 = 1999.

What is the difference between CCCD and the old CMND?

CCCD (Căn cước công dân) is the 12-digit chip-based citizen card that replaced the older 9-digit CMND. This decoder is for the 12-digit CCCD format.

Can it tell me if a CCCD is real or valid?

No. It decodes only the documented structure (province, gender, century, birth year). It has no checksum and never confirms a number actually exists or belongs to anyone.

What if my province code is not recognised?

The tool maps the official 3-digit province codes. A code outside that set is shown as "Unknown province code" while the gender and birth year still decode correctly.

How accurate is the decoding?

The province (3-digit code), gender and birth year follow the documented CCCD structure (Circular 07/2016/TT-BCA) and are accurate for codes in the reference list. The tool never confirms a CCCD number actually exists.

Is my CCCD number sent anywhere?

No. This tool is privacy-first — all processing happens locally in your browser and the number never leaves your device.

Vietnam CCCD Decoder

A Vietnamese CCCD (Căn cước công dân — Citizen Identity Card) is a 12-digit number, and unlike a random ID it is structured: the digits encode the holder’s province of registration, the century and gender, and the birth year. This decoder reads that structure and shows you the province/city, the full birth year, the gender, and the trailing serial. It is useful for understanding your own card or verifying that fields line up.

How it works

The 12 digits follow the format set out in Circular 07/2016/TT-BCA:

Position	Meaning
1–3	Province / city code (mã tỉnh)
4	Gender + century code
5–6	Last two digits of the birth year
7–12	Random serial

The 4th digit is the clever part. Its half (rounded down) gives the century: 1900 + floor(digit / 2) × 100. So 0–1 → 1900s, 2–3 → 2000s, 4–5 → 2100s. Even is male, odd is female. The decoder then adds the two-digit year (positions 5–6) to that century start.

Example

Take 001 0 99 012345:

001 → province Hà Nội
digit 0 → century 1900 + floor(0/2)×100 = 1900s, and even → Male
99 → birth year 1900 + 99 = 1999
012345 → serial

Result: a man from Hà Nội born in 1999. The decoder reads only the documented structure of the number and never checks it against any government database — everything runs locally in your browser.