Home · Learn · How to Make a Barcode: A Practical 4-Step Walkthrough
How to Make a Barcode: A Practical 4-Step Walkthrough
Pick the right format, encode your data, generate, print. The whole flow takes under a minute with the right tool. Here is how, with our generator embedded below.
Making a barcode is genuinely easy — pick a format, type your data, download. The harder part is picking the right format for your use case, because retail (UPC, EAN), inventory (Code 128, Code 39), shipping (GS1-128, ITF-14), and digital (QR Code, Data Matrix) all need different encodings. This guide walks through the four-step flow with format recommendations for each scenario.
One important upstream decision: if your barcode is going on a product that will be sold at retail, you need a GS1-licensed number (UPC, EAN, ISBN) — you cannot legally invent one. Internal-use barcodes (warehouse tags, event tickets, inventory) have no such restriction; you can make whatever Code 128 or QR Code you want, with any data inside.
Step 1: pick the right format
Five common scenarios. (1) Retail product going to a store or marketplace → UPC-A (US/Canada) or EAN-13 (everywhere else). Both require a GS1-licensed number. (2) Internal inventory or warehouse asset → Code 128 (alphanumeric, high density) or Code 39 (older systems). Use whatever data you want. (3) Shipping carton or pallet → ITF-14 (case codes) or GS1-128 (with Application Identifiers like (00) SSCC, (01) GTIN, (10) lot, (17) expiry). (4) Pharmaceutical → GS1 DataMatrix for DSCSA compliance, encoding (01) GTIN + (17) expiry + (10) lot + (21) serial. (5) Digital link or URL → QR Code (mass-market) or Data Matrix (small surfaces, industrial).
Step 2: enter your data
What goes in depends on the format. UPC-A takes a 12-digit number (11 data digits + 1 check digit, which the generator computes). EAN-13 takes 13 digits (country prefix + company prefix + product + check digit). Code 128 and Code 39 take any string — typically a SKU like 'ACME-SHIRT-RED-XL' or a serial number. QR Code takes a URL, a vCard, text, or a Wi-Fi connection string. The generator will warn you if your input is invalid for the selected format (e.g., too few digits, illegal characters).
Step 3: generate and download
Render the barcode as PNG (best for screen and most printers), SVG (best for resizing without quality loss — recommended for packaging design), or PDF (best for labels and Avery sheets). Our generator outputs all three. For batch use, upload a CSV of values and download a ZIP of barcodes — useful when generating hundreds of inventory codes at once.
Step 4: print at the right size and contrast
Size: UPC-A nominal is 1.469″ wide × 1.02″ tall, but the GS1 spec allows 80%–200% scaling. Going below 80% risks scanner failure. Code 128 needs minimum 0.0075″ bar width (X-dimension) for retail scanners; thermal printer barcodes on Zebra/Dymo labels typically use 0.013″ or higher. QR Code minimum scanner-readable is ~10mm × 10mm. Contrast: black bars on white background is the gold standard. Avoid colored backgrounds, glossy laminate over the barcode, or low-contrast color combos — they degrade scan reliability sharply. Always include a quiet zone (white margin) of at least 10x the X-dimension on each side.
Do I need to register with GS1 first?
Only if the barcode is going on a product sold at retail or to wholesale partners that verify against GS1 GEPIR. Amazon, Walmart, Target, Costco, Kroger, and most major retailers verify every submitted GTIN against the GS1 registry — non-GS1 numbers get rejected as 'invalid GTIN'. For internal-only use (warehouse asset tags, employee badges, event tickets, in-house inventory), you do NOT need GS1. You can use any Code 128, Code 39, or QR Code with any data you like.
Making barcodes in Excel, Google Sheets, or Canva
Three common alternative paths. (1) Excel with a barcode font — install a Code 39 font (free), then any cell containing *YOURDATA* in that font renders as a barcode. Cheap but limited to Code 39, no check digit calculation, no UPC support. (2) Google Sheets with the IMAGE() formula pointing at a barcode API — works, but you depend on the API uptime and most APIs rate-limit free use. (3) Canva's barcode app — easy drag-and-drop into design files. Good for small runs. For anything beyond a few dozen, a dedicated generator like ours (free for up to 30/day) is faster and supports more formats.
FAQ
How do I create my own barcode?
Four steps. (1) Pick the format — UPC/EAN for retail, Code 128 for inventory, QR for digital. (2) Enter your data — for UPC, a GS1-licensed 12-digit number; for Code 128/QR, any string. (3) Generate as PNG, SVG, or PDF. (4) Print at recommended size with black-on-white contrast and a clean quiet zone. The whole flow takes under a minute with an online generator.
Can I make my own barcode for my product?
Yes, but the type of barcode depends on where it will be sold. For internal inventory or warehouse use, you can freely make Code 128 or Code 39 barcodes with any data. For retail products (Amazon, Walmart, grocery stores), you must use a GS1-licensed UPC or EAN — invented numbers will be rejected by retailer GTIN verification.
Can I create a UPC barcode for free?
You can generate the barcode IMAGE for free (any online generator, including ours, will render a UPC-A image from a 12-digit number). But the NUMBER itself must come from a GS1-licensed Company Prefix if you intend to sell the product at retail. GS1 charges $30+ for a single GTIN. Free generators issuing real UPCs are scams or use recycled pre-2002 prefixes that fail Amazon/Walmart verification.
What is the best free barcode generator?
Strongest factors: format coverage (does it support UPC, EAN, Code 128, QR, Data Matrix), output formats (PNG, SVG, PDF), check-digit calculation, and bulk-mode CSV upload. Major free options include our generator (full coverage, CSV bulk, PDF sheets), TEC-IT (very broad format support), and OnlineLabels (best for printing to physical label sheets). Canva is fine for one-off design work but lacks bulk and PDF sheet output.
Can I make my own UPC barcode?
You can render the barcode image yourself, but the underlying 12-digit number must come from GS1. Amazon, Walmart, Target, and Costco all verify submitted UPCs against the GS1 GEPIR registry — invented numbers fail verification and the product listing is rejected. Buy directly from gs1us.org if you need real UPCs for retail.
Can a phone be used as a barcode scanner?
Yes — every smartphone camera from the last decade can scan 1D barcodes (UPC, EAN, Code 128, Code 39) and 2D codes (QR, Data Matrix). iPhone scans QR natively via the camera app; Android uses Google Lens. For inventory work, free apps like Orca Scan or Scandit add scan-to-spreadsheet workflows. Hardware scanners are still faster for high-volume use (>100 scans/day) but a phone is fine for most small-business use.
Related generators
Need a real barcode now?
Generate a valid UPC-A barcode in seconds — no signup, no watermark. Free for casual use; paid plans from $9/mo for higher volume.