Tracking Label

Tracking labels are used to track individual parcels that move through the last mile of the parcel journey.

Label Requirements

Barcode Requirements

A GS1 Serial Shipping Container Code (SSCC) compliant barcode and corresponding human-readable serial reference must be included on the tracking label. Be sure to check that it can be scanned easily by the carrier.
A Company Prefix range will be issued to you by Parcelpoint, however, if you wish to use your own range, you will need to inform Parcelpoint to see if that range is available.
The barcode must meet the following requirements:

• Be in GS1-128 format (or at the very least use Code-128 format)
• Be at least 78mm width
• Be at least 26mm height
• Human-readable SSCC Number should have a font size of at least 10pt
• Spacing around the barcode should be at least 5mm of white space

A GS1-128 SSCC barcode must include the following structure:

• Parcelpoint will supply you with a Extension Digit and Company Prefix
• The Serial Reference can be any numerical serial that is 8 digits in length (99.9M barcodes)

An example of a barcode would be as follows:

How to generate the SSCC

To generate the SSCC, use the generateSSCC function:

function generateSSCC(i) {
	var extDigit = '1', // Parcelpoint to supply Ext. Digit
    	companyPrefix = '93499680', // Parcelpoint to supply Company Prefix
    	barcode = extDigit + companyPrefix + generateSerial(i);
    	sscc =  barcode + generateChecksum(barcode);
    
    console.log(sscc + " " + isValidSSCC(sscc));

    return sscc;
}

How to calculate the checksum

• The check digit is mathematically calculated and ensures the whole number is correct.
• Instructions for calculating the check digit are available from GS1 (Note: The AI (00) is not part of the Check Digit calculation)
• Check digit computation rules are on p465-466 of GS1 General Specifications Version 15 (issue 2), Jan-2015
• You can use the online check digit checker

To generate the checksum, use the generateChecksum function:

function generateChecksum(barcode) {
    var arr = barcode.substring(0,barcode.length).split("").reverse();
    var oddTotal = 0, evenTotal = 0;

    for (var i=0; i<arr.length; i++) {
    	if (isNaN(arr[i])) { 
        	return false; 
        } 
        else if (i % 2 == 0) { 
        	oddTotal += Number(arr[i]) * 3; 
        } 
        else { 
        	evenTotal += Number(arr[i]); }
        }
        
        checkSum = (10 - ((evenTotal + oddTotal) % 10)) % 10;
        return checkSum;
}

Checking the barcode for errors

It's recommended that spot test your barcode to make sure that the barcode is being generated correctly.

To test if the SSCC is valid use the isValidSSCC function:

function isValidSSCC(sscc) {
    if (sscc.length < 8 || sscc.length > 18 ||
        (sscc.length != 8 && sscc.length != 12 && sscc.length != 13 && sscc.length != 14 && sscc.length != 18)) {
        return false;
    }

    let lastDigit = Number(sscc.substring(sscc.length - 1));
    let checkSum = 0;
    
    if (isNaN(lastDigit)) {
    	return false;
    }

    let arr = sscc.substring(0,sscc.length - 1).split("").reverse();
    let oddTotal = 0, evenTotal = 0;

    for (var i=0; i<arr.length; i++) {
        if (isNaN(arr[i])) {
        	return false;
        }
		else if (i % 2 == 0) {
        	oddTotal += Number(arr[i]) * 3;
        }
        else {
        	evenTotal += Number(arr[i]);
        }
    }
    
    checkSum = (10 - ((evenTotal + oddTotal) % 10)) % 10;
    return checkSum == lastDigit;
}