A TypeScript/JavaScript library for generating, validating, and parsing 🇨🇿Czech and 🇸🇰Slovak birth numbers (rodné číslo). Built for reliability, performance, and ease of use.
npm install @ppasmik/birth-number-utils
import { generateBirthNumber } from '@ppasmik/birth-number-utils';
// Generate a random birth number
const randomBirthNumber = generateBirthNumber();
console.log('Random Birth Number:', randomBirthNumber); // e.g., "900720/3117"
// Generate using string date (recommended)
const birthNumber1 = generateBirthNumber({
gender: 'MALE',
birthDate: '1985-11-19', // November 19, 1985 (YYYY-MM-DD format)
});
// Generate using Date object (note: months are 0-based in JavaScript Date)
const birthNumber2 = generateBirthNumber({
gender: 'FEMALE',
birthDate: new Date(1990, 6, 20), // July 20, 1990 (month 6 = July)
});
- When using string dates (recommended): Months are 1-based (1 = January, 12 = December)
- When using JavaScript Date object: Months are 0-based (0 = January, 11 = December)
- Examples:
// These create the same birth number (November 19, 1985):
generateBirthNumber({ birthDate: '1985-11-19' }); // string format
generateBirthNumber({ birthDate: new Date(1985, 10, 19) }); // Date object (10 = November)
import { isValidBirthNumber } from '@ppasmik/birth-number-utils';
// Validate birth numbers
console.log(isValidBirthNumber('9007203117')); // true
console.log(isValidBirthNumber('9902291118')); // false (invalid date)
import { parseBirthNumber } from '@ppasmik/birth-number-utils';
// Parse a valid birth number
const parsed = parseBirthNumber('9007203117');
if (parsed) {
console.log('Parsed Birth Number:', parsed);
// { birthDate: Date, gender: 'MALE', age: 33, ... }
} else {
console.log('Invalid birth number.');
}
// Attempt to parse an invalid birth number
const invalidParse = parseBirthNumber('9902291118'); // 29th Feb 1999 does not exist
console.log('Parse Result:', invalidParse); // false
- Generate valid birth numbers following Czech/Slovak standards
- Validate existing birth numbers for correctness
- Parse birth numbers to extract information such as birth date and gender
- Supports both formatted (with `/`) and raw formats
- TypeScript support with strong typing for all APIs
- Comprehensive test coverage for edge cases
- Uses dayjs for robust date handling
Options:
gender
:'MALE' | 'FEMALE'
(Optional, defaults to a random gender)birthDate
:Date
(Optional, defaults to a random date between 90 and 18 years ago)
Returns:
- A birth number in the format
YYYYMM/DDXX
(following Czech/Slovak standards)
Parameters:
birthNumber
: A string containing the birth number to validate (formatted or raw)
Returns:
true
if the birth number is validfalse
otherwise
Parameters:
birthNumber
: A string containing the birth number to parse (formatted or raw)
Returns:
- An object containing birth date, gender, and other details if valid
false
if the birth number is invalid
For more complex operations, you can use the BirthNumber
class or rodnecislo
factory function:
import { rodnecislo, BirthNumber } from '@ppasmik/birth-number-utils';
// Using factory function
const rc = rodnecislo('900720/3117');
// Or using class directly
const bn = new BirthNumber('900720/3117');
// Available methods
rc.isMale(); // true/false
rc.isFemale(); // false/true
rc.year(); // returns year (e.g., 1990)
rc.month(); // returns zero-based month (0-11)
rc.day(); // returns day of month (1-31)
rc.birthDate(); // returns Date object
rc.birthDateAsString(); // returns date in DD.MM.YYYY format
rc.isValid(); // true if valid and not in future
rc.isPossible(); // true if valid (even if in future)
rc.isAdult(); // checks if age >= 18
rc.isAdult(21); // checks if age >= custom value
rc.age(); // returns current age
rc.error(); // returns error message or null
We welcome contributions to enhance this library. If you find a bug or have an idea for improvement, feel free to open an issue or submit a pull request.
Please make sure to include tests for your changes.
MIT © [Peter Pasmik]