Introduction

UK number plates are available in a set range of formats. This short Node JS validation script will take a supplied string and return to you a JSON object containing a correct/road legal formatted version of the registration plus some other useful information where possible.

There's a full guide at Capital Reg on the various UK number plate formats.

Installation

  npm install uk-numberplates

Usage

Very simple - the short of it is that you include the uk-numberplates module, then you're able to feed the validate function a string you'd like to be parsed/validated, and provide a callback function. The callback function receives two values, an error flag (false if all is OK and the string was parsed as a valid registration mark) and a JSON data object containing the correctly formatted number plate along with any additional info.

Here's a quick example that runs through an array and validates the registrations it contains.

// Include the module...
validation = require('uk-numberplates');

// Build an array of scrambled registrations to work with...
var registrations = new Array();
registrations.push('a123sTe');
registrations.push('a1');
registrations.push('BAZ76');
registrations.push('rgbHEX');
registrations.push('999tst');
registrations.push('ab98ste');

// Loop each registration and run it through the validator...
for(var i = 0; i<registrations.length; i++) {
	var reg = registrations[i];
	validation.validate(reg, function(err,data) {

		console.log('Registration checked = ' + reg);
		console.log('Response: ');
		console.log('Error: ' + err);
		console.log(data);
		console.log('-----------------------------');

	});
}

Response

If the error value returned is false, then the string parsed was determined to be a valid registration. If anything is else is returned, this is a hint as to why the string is not valid.

• 1 = UNKNOWN FORMAT - Whatever this string is, it doesn't approach a legal UK number plate format.
• 2 = INVALID CHARS - UK number plates are characters A-Z, numbers 0-9 and a space; nothing else.
• 3 = ASTERISK - the string contained an asterisk.
• 4 = Q IN REG (NOT PREFIX) - the letter Q is only issued to a limited subset of 'prefix' number plates. This string contained a Q but wasn't a match to the prefix format.
• 5 = I BUT NOT IRISH - The letter I is reserved for use on Irish number plates, this string contained an I, but wasn't Irish in format.
• 6 = Z BUT NOT IRISH OR NEW STYLE - The letter Z is reserved for use on Irish and new style (post 2000) number plates. This string contained Z but matched neither format.
• 7 = NEW STYLE Z IN FIRST 2 CHAR - New style registration format, but the letter Z was detected in the first two characters of the plate. Z is only valid in the last three.
• 8 = INVALID NUMBER (LEADING ZERO) - UK number plates do not have a leading zero (the exception being the new style format - but this string must not have matched that format).

The JSON data object returned looks something like this :

{ plate: 'A123 STE',
  irish: false,
  prefix: 'A',
  suffix: 'STE',
  number: '123',
  year_of_issue: '1983',
  year_of_issue_expiry: '1984',
  month_of_issue: '08',
  month_of_issue_expiry: '08' }

• The plate value is the correctly formatted registration - in this case the string fed in could be mapped to A123 STE.
• irish is a true or false value that identifies if the registration is Irish in origin.
• prefix, suffix and number represent the component parts of this registration. In this example 'A' is the prefix letter, 'STE' the suffix, and '123' being the numbers. In the case of suffix format reg - such as 'STE 123A' - these values would be the same, but of course prefix effectively means suffix, whilst suffix effectively means index, as the registration is 'flipped'. With a dateless registration that carries no prefix, prefix would be false and suffix would also effectively mean index.
• year_of_issue tells you what year this registration would first have been available - for as yet unreleased plates the future release date will be calculated (e.g 'AB98 STE' = 2048).
• month_of_issue tells you the month of the year this registration would have first been available.
• year_of_issue_expiry and month_of_issue_expiry tell you when the following sequence of number plates was released that suprceeded reg of this type (e.g 'A' reg came out in 1983, 'B' reg followed in 1984).

The year/month of issue dates are NOT always available. Dateless number plates have no identifiers to give their age. In this case a value of 'DAT' signifying 'dateless' will be returned.