Inventory App Builder

Barcode basics for small shops: UPCs, in-store labels, scanners and printers (2026)

When a small shop needs GS1 barcodes and when its own labels will do, what GS1 US charges, which barcode types to print, and how to choose scanners and label printers.

Floot ·

Key Takeaways

  • A barcode is just a way of writing a number. GS1 US puts it simply: the barcode is the carrier, the GTIN is the data. What matters is which number you encode.
  • Resell branded goods? Use the barcode already on them. Products from manufacturers usually arrive with a UPC or EAN. Scan it into your system against your SKU rather than relabelling.
  • Make your own products for other retailers? You need GS1 numbers. GS1 US licenses a single GTIN for $30 with no renewal fee, or a company prefix from $250 plus $50 a year for up to 10 items.
  • For in-store use only, print your SKU. Code 128 or QR codes encoding your own SKU work fine on shelf labels and back-room bins. They are not valid as UPCs outside your shop.
  • Test with your real labels and devices. Print a sheet, scan it with every phone and scanner you’ll use, on curved and shiny surfaces, before labelling the whole shop.

Quick-Start Prioritization Framework

Your situationWhat to useCost to get numbers
You resell branded productsThe manufacturer’s existing UPC/EANNothing
You make products sold only in your shopYour own SKU printed as Code 128 or QRNothing
You make a few products for other retailers or marketplacesGS1 US single GTINs$30 each, no renewal (GS1 US)
You make 10+ products for wholesaleGS1 Company PrefixFrom $250 + $50/year for 10 items (GS1 US)
Shelf, bin and location labelsCode 128 or QR with a location codeNothing

Barcodes speed up three jobs in a shop: ringing up sales, receiving deliveries and counting stock. They also confuse a lot of owners, because “barcode” is used for two different things: the global product numbers that manufacturers license from GS1, and the labels any shop can print for its own use. This guide separates the two, explains when you need to buy official numbers and what they cost, which formats to print for in-store use, how to pick scanners and label printers, and how to test the whole setup before you rely on it.

GTINs, UPCs and barcodes: getting the words straight

A GTIN (Global Trade Item Number) is a product number licensed through GS1, the standards body behind retail barcodes. A barcode is the pattern of bars that lets a scanner read a number quickly. GS1 US explains that a UPC-A barcode carries a 12-digit GTIN-12, and an EAN-13 barcode carries a 13-digit GTIN-13, more common outside North America.

The formats you’ll meet

GTIN-12 (UPC-A): 12 digits, the standard retail barcode in North America. GTIN-13 (EAN-13): 13 digits, used mainly elsewhere. GTIN-8: for very small packs. GTIN-14: for cases and cartons, not meant to be scanned at a till. GS1 US describes all four.

Every variant needs its own number

GS1 US says each distinct variation you sell, such as a different size, flavour or packaging, needs its own GTIN. The same logic applies to your SKUs: if you count it separately, it needs a separate code.

Where your SKU fits

Your SKU is your own internal code. In your inventory system, each SKU can store one or more GTINs, so scanning the manufacturer’s barcode finds your SKU. That link is what makes scanning useful.

Do you need to buy GS1 barcodes?

Most small shops that resell other people’s products never need to buy a single GTIN. The question only arises when you make or brand products yourself.

OptionInitial feeAnnual renewal
1 GS1 US GTIN$30$0
Company Prefix, up to 10 items$250$50
Company Prefix, up to 100 items$750$150
Company Prefix, up to 1,000 items$2,500$500
Company Prefix, up to 10,000 items$6,500$1,300

When you probably don’t

You resell branded goods that already carry a barcode. You make products that you only sell in your own shop or on your own website. You only need labels for shelves, bins or internal tracking.

When you probably do

Another retailer, a distributor or a marketplace asks for a UPC or GTIN for your products. Each one sets its own rules, so check their requirements in writing before you buy. If they ask for a GS1-issued number, a home-made barcode won’t do.

What GS1 US charges

GS1 US lists these prices on its how-to-get-a-UPC page, and notes it reserves the right to change them.

Single GTINs vs a company prefix: worked numbers

The break-even depends on how many products you will number and for how long.

A maker with 6 products

Six single GTINs cost 6 × $30 = $180, once. A 10-item prefix costs $250 plus $50 a year, so $400 over four years. Single GTINs win comfortably.

A maker with 40 products

Forty single GTINs cost 40 × $30 = $1,200, once. A 100-item prefix costs $750 plus $150 a year: $1,350 after two years and $1,650 after four. Single GTINs are cheaper at first; the prefix leaves room to grow to 100 items, but costs more over time if you stay near 40. Run the numbers for your own plans, and remember new variants each need a number.

Restrictions on single GTINs

GS1 US notes that single GS1 US GTINs are not available for pharmaceutical products, variable-measure products such as goods sold by weight, mixed cases or coupons.

How a UPC check digit works

The last digit of a UPC is a check digit calculated from the other eleven. Scanners use it to catch misreads. You will never calculate one by hand in practice, but knowing how it works explains why a single wrong digit fails to scan.

Worked example

Take the first eleven digits 0 3 6 0 0 0 2 9 1 4 5. Add the digits in odd positions (1st, 3rd, 5th and so on): 0 + 6 + 0 + 2 + 1 + 5 = 14, and multiply by 3 to get 42. Add the digits in even positions: 3 + 0 + 0 + 9 + 4 = 16. Total 42 + 16 = 58. The check digit is whatever brings that up to the next multiple of 10: 60 − 58 = 2. The full UPC is 036000291452.

Why it matters to you

If staff type a barcode by hand when a label won’t scan, a good system checks the digit and rejects a typo instead of selling the wrong item.

Labels for your own use: Code 128 and QR codes

For products without a barcode, shelf edges, back-room bins and storage locations, print your own labels that encode your SKU or a location code.

Code 128

A linear barcode that encodes letters, numbers and hyphens, so it can carry a SKU like CND-LAV-08-01 directly. Almost every scanner reads it, and it fits on narrow shelf labels.

QR codes

Square codes that phone cameras read easily from any angle. Good for bins, storage shelves and items you scan with a phone rather than a dedicated scanner. They need more square space than a linear barcode.

Put the human-readable code on too

Print the SKU and a short product name under the barcode. When a label is scuffed or a scanner is flat, staff can still find the item by typing the code.

Scanners and label printers

You don’t need specialist hardware to start, but the right devices make daily work noticeably faster.

Phone cameras

Many inventory and POS apps scan with the phone’s camera. Sortly, for example, lists in-app barcode and QR code scanning from a smartphone. Cameras are fine for counting and receiving at a moderate pace; they are slower than a scanner at a busy till and struggle in poor light.

USB and Bluetooth scanners

Most handheld scanners act like a keyboard: they “type” the number into whatever field has focus, followed by Enter. That makes them work with almost any software, including spreadsheets and web apps. Check that the model reads the symbologies you print, and that its Bluetooth pairing works with your tablet or phone.

Label printers

Thermal label printers print barcodes crisply without ink. Direct thermal labels are cheaper but fade with heat and sunlight, which suits short-lived price tags. Thermal transfer uses a ribbon and lasts longer, which suits bin and shelf labels. Some POS plans include label printing; Square, for example, lists barcode label printing on its Plus and Premium plans.

Rolling barcodes out in your shop

Start where scanning saves the most time, and expand from there.

1. Link existing barcodes to your SKUs

Scan one of each branded product into your system so its UPC is stored against your SKU. Do this as deliveries arrive rather than in one marathon session.

2. Label what has no barcode

Print SKU labels for your own products and anything unlabelled, starting with best-sellers.

3. Test before you trust

Print a test sheet. Scan each label with every device you’ll use, from different distances, on curved jars and shiny packaging, and in the dimmest corner of the shop. Leave a clear margin (quiet zone) either side of linear barcodes, and don’t shrink them to fit.

4. Use scanning for receiving and counting

Scanning at the till is the obvious use. Scanning deliveries against the purchase order and scanning during cycle counts often save more errors, because those are where similar-looking variants get mixed up.

Common mistakes

These cause most barcode headaches in small shops.

  • Covering a manufacturer’s barcode with your own label, which breaks scanning for anyone else in the supply chain.
  • Printing your SKU in UPC format and assuming it is a valid UPC. Only GS1-licensed numbers are.
  • One barcode for several sizes or colours, so scans can’t tell variants apart.
  • Buying numbers from a reseller without checking whether the retailer or marketplace you sell to accepts them.
  • Shrinking barcodes to squeeze them onto small labels until they stop scanning reliably.
  • Using direct thermal labels on shelves that get afternoon sun.
  • Labelling the whole shop before testing the labels with every scanner and phone you use.

Frequently Asked Questions

Do I need a UPC barcode to sell in my own shop?

No. For products sold only in your shop, your own SKU printed as a Code 128 or QR label is enough. You need GS1-issued numbers when another retailer, distributor or marketplace requires them.

How much does a UPC barcode cost?

GS1 US lists a single GTIN at $30 with no annual renewal. A company prefix for up to 10 items costs $250 plus $50 a year, and up to 100 items costs $750 plus $150 a year. GS1 US may change these prices.

What is the difference between a SKU and a UPC?

A UPC is a 12-digit global product number licensed through GS1 and usually assigned by the manufacturer. A SKU is your own internal code. Your system can link the two so scanning a UPC finds your SKU.

Can I use my phone as a barcode scanner?

Yes, with apps that support camera scanning. It works well for counting and receiving. At a busy till or in poor light, a handheld scanner is usually faster and more reliable.

Should I use barcodes or QR codes for inventory?

Use the manufacturer’s barcodes on products that have them. For your own labels, Code 128 suits narrow shelf labels and handheld scanners; QR codes suit bins and phone-camera scanning. Many shops use both.

Can I build my own app with barcode scanning?

If you’d rather not use an off-the-shelf tool, an AI app builder such as Floot can build an inventory app and you can ask it to add a camera scanning screen. Test it carefully on the actual phones your staff use, with your real labels, before relying on it.

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