How Does a Barcode Work? 


If you are completely new to how barcodes work, we are here to help. You may have an existing barcode system and want to know how to expand it or optimise it better, or perhaps you want to upgrade to a more sophisticated barcode system.

For expert advice and assistance on how to upgrade your barcode system, or to install a barcode system for the first time to make your business commercially successful, contact ProSku for the best professional advice. We invite you to compare all the various barcode reader systems and WMS software options.

Call us on 0800 170 1161 or email us at for more information.


What is a barcode in simple terms?

Barcodes use modern technology to store vast amounts of information about products, manufacturers, distributors and shipping details, in coded form on a label the size of a postage stamp or smaller.

Barcode scanners read these codes from labels adhered to each product and send them to a computer equipped with sophisticated software that analyses, interprets, computes, and updates the data, all in a fraction of a second, and prints any paperwork you require.

In a modern world, where improved transaction speed, accuracy of storage and real-time data updating are imperative to the success of any business, we can no longer operate with manually updated systems and processes. Manual systems are prone to errors, are cumbersome and time-consuming, and are not cost-effective.

Barcodes have become ubiquitous in any business and we see them on groceries, library books, airline tickets, software applications, delivery notes, invoices, spare parts, and in fact, on virtually everything we use in our daily lives.

No warehouse, retail store, wholesale store, convenience store, manufacturer, distributor, or online business can afford to be without a barcoding system.


What do all the lines, dashes, dots, spaces, shapes, numerals, and characters on a barcode label mean?

Think of a highly sophisticated Morse Code that uses all kinds of machine-readable representations to code and decode vast amounts of information. This information includes details about item descriptions, size and dimensions, colour, price, markup and profit margin, discount tiers, stock levels, manufacturer’s and supply chain details, location on your warehouse shelves, all manner of instructions, software applications, and much more.

Each of the lines of various thicknesses and lengths, dashes, dots, spaces of different widths, and a variety of geometric shapes, numerals, and characters, is assigned a special meaning by a computer, much like letters of the alphabet in different positions would spell different words, and these patterns are then printed onto labels.

The outer two lines and the one in the centre, are called guard bars which tell the computer and barcode scanner when the codes begin and end, and the two numbers outside the white bars of the guard tell the software whether the code is the right way up.

A barcode scanner reads the pattern on the barcode label and sends it to a computer that decodes the pattern and gives you all the information you require about the product, and the information can be printed on a screen or paper in ordinary language.


How does a barcode scanner read a barcode label?

An incandescent light bulb or laser light

Most barcode scanners use a laser light or incandescent light bulb to illuminate the barcode label. The black parts of the pattern absorb the light while the light is either reflected or shines through the white parts, onto a super-sensitive light detector that detects and analyses the light pattern.

When using laser scanners, laser beams are reflected off a mirror, sweeping across the label to read the barcode. This allows reading wider barcodes and from further away.

The scanning engine translates the light impulse into data, much the same as your computer screen or smart device translates an electric impulse typed on the keyboard, into digits you can read.


Range of barcode scanners

Barcode scanners vary in complexity and sophistication. Most smart devices can read barcodes, up the scale to two-dimensional area barcode scanners which take detailed pictures of any barcode and analyse them.

These scan engines can capture the picture in any direction and are highly accurate and super fast.


What are the different types of barcode systems?

Different types of barcodes are used, depending on the complexity of the product and the amount of information that needs to be stored on the barcode label.

This information is used for identifying products, inventory tracking, locating specific items, ordering new stock, inventory control, point-of-sale, pricing, profit margins, discount levels, tracking inventory amounts, and much more.

Numeric and alpha-numeric barcodes.

The first tier consists of one-dimensional labels using numeric or alpha-numeric digits, characters, lines, and spaces of varying widths, and 95 evenly spaced columns, on a white background, each representing separate, detailed data.


UPC and EAN barcodes

The most common barcodes, named UPC (Universal Product Code) and EAN (Originally European Article Number, but this has been extended to International Article Number codes, set by the global standards organization and used in global trade) use a 12- or 13-digit number that represents different types of data.

The first number is the product type, the following 5 numbers are a unique identifier of the manufacturer code or distributor code, the next 5 numbers describe the particular product, and the final number is a self-checking digit that allows the barcode reader and computer to determine if the barcode is correctly composed.


Code 39 and 128 barcodes

Code 39 and 128 barcodes contain variable numbers of digits or characters, depending on the amount of data required but like the UPC barcodes and EAN barcodes, each barcode and set of numbers or digits denote specific types of information.

Code 39 uses 43 characters, consisting of uppercase letters, numeric digits, and special characters. Code 128 is a high-density, barcode technology that uses alphanumeric or numeric-only characters which can encode all 128 ASCII characters.


Two-dimensional QR and data matrix codes

QR codes (quick response codes) are used for more complex data storage and in addition, have interactive capabilities, redirecting the user to a website, online user manual, or app store.

QR codes and data matrix codes make use of a complex combination of short lines, dots, and geometric shapes arranged in a grid, while some include data matrix codes which are used in electronics and logistics.

They are called two-dimensional because hundreds of times more information can be stored on both the vertical and horizontal planes. 2D codes are omnidirectional and can be read from any angle.

Uses of QR and data matrix codes

QR and data matrix codes are very popular in wholesale, retail, and computer application industries because they can be scanned by consumers with smartphones.

They can store information such as brand name, model number, maintenance records, telephone numbers, login details, online account information, and links to websites.

They are also widely used for warehouse inventory management software, maintenance, transportation, health and medical industries, the travel industry, software applications and playstores.


PDF417 code

PDF-417 is a specialist rectangular 2D barcode that uses stacked linear rows of up to 90, each of which is comparable to a linear barcode.

PDF is a common data format and the “417” indicates that the visual pattern consists of 4 bars of black and white bars in space in a pattern that is 17 modules long.

What are PD417 codes used for?

Because they store personal and other important additional data and are extremely useful in document management, they are commonly used in driver’s licences, ID cards, passports, the transportation industry, and in certain warehouses for inventory management.


How are barcodes generated?

There is special software that automatically generates unique machine-readable barcodes for each individual product, using information entered by the user.


Why should your warehouse use barcodes?

No business is too small to benefit from barcodes to improve efficiency and enhance the professional image of your business.


Cost-effective and easy-to-install

A barcoding system is relatively cheap to install and maintain, and will more than pay for itself in providing quick and accurate information at the point of sale, inventory management, and supply chain management.

A barcoding system can be fully integrated with ProSku WMS software as a cost-effective modular add-on.


Benefits of barcodes

How Does a Barcode WorkFor inventory management, an integrated barcode system eliminates the need to manually count and record individual products and drastically reduces the chances of human error.

You can digitally store vast amounts of sales data and other important information about each product in your warehouse, which is instantly available to streamline operations and maximise profits.

Unlike paper records which are incredibly cumbersome to maintain, digital barcode data takes up absolutely no physical space.


Staff training

It is important to train staff how to effectively and efficiently use the barcode system, but it is incredibly easy to understand and training will not take long.

Most modern barcode scanners are incredibly user-friendly and can easily be managed by even the least tech-savvy employee.


What are the disadvantages of barcodes?

Human error

If an error is made in creating the barcode, it might well affect the entire product range, but once identified, is quick and easy to correct on the system.

It is good practice to double-check all entries before generating the barcode labels. Sophisticated barcoding software like ProSku, has error-checking capabilities, further reducing human error.

Cost of hardware

Depending on the nature of your business, several expensive barcode scanners and other hardware may be required. Once again, the benefits by far outweigh the disadvantages of the capital costs and in terms of efficiency and labour saving, they will soon pay for themselves too.

Damaged or faded labels

If barcode labels fade or are damaged, it will be difficult to identify the product. It is very important to ensure the correct labels are adhered to the product in a position that is easily located and read by the barcode scanner.

Frequently inspect the labels and ensure they synchronise with the software system. When special offers or seasonal changes, temporarily change the price or other information about the product code, ensure the system is amended accordingly.


How will a barcode system help my business?

There are so many ways in which a barcode system will benefit your business, but here are a few of the most important functions:

Inventory identification and tracking

Barcodes make it a simple matter to enter new items into your own inventory tracking database and keep track of the location, all movements, stock levels, orders, shipping, and delivery.


Barcodes can be linked to orders and invoices for greater accuracy, expediting the fulfilment process, and automatically adjusting stock levels.

The operator simply needs to scan the barcode on the invoice to locate items for picking, where they are located, and what equipment is required to access and package the items for delivery.

Shipping and delivery

By scanning the barcode upon acceptance for shipping or delivery, the operator will instantly identify the correct parcel. It makes it simple to accurately keep track of the delivery status.

Storage, picking and shipping merges

Barcodes can easily be created for batches of products, linking them to each other according to the data fields you choose.


Is there an alternative to barcodes?

RFID (Radio frequency identification) is a fully automated alternative to barcodes that seamlessly integrates with ProSku WMS software.


Which is the best barcode system for my business?

Your choice will enable you to make better business decisions, streamline your operations, and speed up your service delivery.

At ProSku, we can help you to compare all the various barcode scanner systems and WMS software options. Contact us online or call us on 0800 170 1161 to book a demo. You can also email us for more information.