rodnecislo
A npm package for validating and deriving information from Czech and Slovak National Identification Number. This number is used in Czech and Slovak Republic as the primary unique identifier for every person by most, if not all, government institutions, banks, etc. It consists of two parts: birth date (with gender mark) and serial number with check digit. It is commonly known as Birth Number or rodné číslo in both Czech and Slovak hence the library name.
Install
Works with nodejs v10 and higer (ES2015).
npm install rodnecislo
Usage
;// let { rodnecislo } = require("rodnecislo") let rc = rc // truerc // false rc // 2011rc // 11 - zero based monthrc // 13 rc // new Date(2011, 11, 13) - "Tue Dec 13 2011 00:00:00 GMT+0100 (CET)"rc // "13.12.2011" - the Czech date format rc // truerc // true (valid, but maybe in the future) rc // false - by default checks if current date is above 18 years oldrc // false - for US rc // 5 - age today (it is 5.6.2017 ;) rc // "CZ1112133121" - Czech Tax Identification Number (DIč)
Definitions and legislation
Dictionary
- birth number - National Identification Number in Czech and Slovak republic
- birth date part - first 6 digits of birth number, typically divided with serial number with slash '/'
- serial number - 3 digits diferentiating people born on the same day, occurs after '/'
- check digit - last digit of the birth number, making it divisible by 11 (with exceptions)
- DIC - czech VAT number
Historical evolution
Before 1953
- People in Czechoslovakia have Personal ID Card Number or Work ID Card Number. It isn't called birth number/rodne cislo yet.
- It has format
yymmdd/sss
- Women have
mm+50
sss
is serial number for people born on the same day- Eg:
516231/016
is birth number of a female, born on 31 Dec 1951
After 1953
- Birth number is official now
- It has format:
yymmdd/sssc
- Women have:
mm+50
- Whole PIN must be divisible by 11 OR
- If
(yymmddsss % 11 == 10 && c == 0)
then the birth number is valid
After 1985
- The
(yymmddsss % 11 == 10 && c == 0)
exception was removed - ... every new birth number must be divisible by 11 as a whole from now on
In 1993 Czechoslovakia split into Czech Republic and Slovak Republic
- the legislation might differ from this point on
After 2004
- Since 2004 (law nr. 53/2004) it is possible to add extra 20 to the month number in case the number
of newborns exceeds all the possible combinations of birth date/birth number divisible by 11.
In conclusion:
- Men can also have
mm+20
- Women can also have
mm+70
- Men can also have
So to wrap it up
Short/long version
- Short version was used before 1953
- Long version AND
yy >= 54
THENyyyy = 19yy
- Long version AND
yy < 53
THENyyyy = 20yy
- Who knows what comes in 2053...
Month/Gender
- Month is
51-62
OR71-82
- female, subtract50
and70
respectively - Month is
01-12
OR21-32
- male, subtract20
Modulo condition
- Short birth number - no modulo condition
- Whole birth number is divisible by 11 - valid birth number
- Whole birth number without check digit modulo
11
equals10
AND check digit is0
AND year is54-85
- valid birth number
Age and Adultood
According to Civil code §601 law n. 89/2012 and §30 of New Civil Code an age is reached at midnight which is starting the birthday. So on the first seconds of your 18th birthday you can start drinking in Czech.
VAT Identification Number
In Czech the personal VAT Identification Number
is derived from Birth Number by adding CZ
prefix and ommitting the slash.
It is called Daňové identifikační číslo (DIČ)
hence the .dic()
method.
Sources
Specification comes mainly from following links:
- Rodné číslo - sk wiki
- Rodné číslo - cz wiki
- National identification number - Czech and Slovak birth number - en wiki
- Educational web of Miroslav Lorenc
- Czech Civil Code
RegExp
RegExp for rodné číslo. With/without slash.
| 1 | 2a | 2b | 2c | 2d | 3 |4 | 5 |
/^\d{0,2}((0[1-9]|1[0-2])|(2[1-9]|3[0-2])|(5[1-9]|6[0-2])|(7[1-9]|8[0-2]))(0[1-9]|[1-2][0-9]|3[01])\/?[0-9]{3,4}$/;
Explanation:
- 1 - 00-99 birth year, i.e.
yy
- 2 birth month, i.e.
mm
- a - 01-12 for men
- b - 21-32 for men*
- c - 51-62 for women
- d - 71-82 for women*
- 3 - 01-31 birth day, .i.e.
dd
- 4 - slash
- 5 - 000-9999 serial and check digit, .i.e
xxxx
Unanswered Questions
- What happens to birth number in 2053?
- How many colisions in birth number are there?
Author
Jakub Podlaha j.podlaha@gmail.com
License
MIT : http://opensource.org/licenses/MIT
Contributing
Don't hesitate to let me know about errors and/or possible uselessnesses. I did this for my project first but would be glad if others find this useful.