Barcode Generator

Pick a symbology, type your data, and the barcode redraws as you go. Everything runs in your browser — nothing you enter is uploaded.

Barcodes, symbology by symbology

A barcode is just a machine-readable rendering of a short string. Thesymbology is the rulebook that says how characters become bars (or, for 2-D codes, cells) — which characters are allowed, how long the data can be, and whether a check digit is required. Picking the wrong symbology is the most common reason a scanner at the other end refuses to read a code, so start from what the code is for.

Where it is usedTypical symbology
Retail point of saleEAN-13, EAN-8, UPC-A
Cartons, cases and logistics unitsITF-14, GS1-128, GS1 DataBar
Warehouse, asset tags, internal labelsCode 128, Code 39
Books and journalsISBN (Bookland EAN), ISSN
Mail and parcelsUSPS Intelligent Mail, POSTNET
Event tickets, boarding passes, IDAztec, PDF417
Marketing, links, app installsQR Code
Small parts, electronics, medicalData Matrix, DotCode
Pharmacy packagingPharmacode, GS1 DataBar, Data Matrix

Quiet zones

Every linear barcode needs a blank margin — the quiet zone — before the first bar and after the last. A scanner uses that clear space to lock onto the edges of the symbol; without it the first or last character is misread or the whole code is skipped. The rule of thumb for 1-D codes is a margin at least ten times the width of the narrowest bar; QR and Data Matrix want a border of about four cells. The quiet-zone toggle above adds a standards-friendly margin. The only time to turn it off is when you are dropping the code into your own layout and will add the margin there.

Check digits

A check digit is one extra character derived by arithmetic from the rest of the data. The scanner recomputes it and compares; a mismatch means a misread, and the scan is rejected rather than passed on wrong. EAN-13, EAN-8, UPC-A and ITF-14 all self-check this way using the GS1 mod-10 formula. This tool computes those locally: give it the body of the number and it appends the correct final digit, or give it the full code and it confirms the digit — and names the one it expected if you have a typo. Code 39, Code 128 and the 2-D symbologies carry their own internal error checking, so you do not add anything by hand.

PNG or SVG

Download a PNG for screens, spreadsheets and slide decks — raise the scale first if it is going to print. Download anSVG for anything that will be printed properly or edited later: it is vector, so it stays crisp at any size and opens in any design tool.

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Frequently asked questions

Which barcode should I use?
Retail point of sale uses EAN-13 (or EAN-8 for tiny packs) and UPC-A in North America. Cartons and pallets use ITF-14 or GS1-128. Internal warehouse, asset and label jobs use Code 128 or Code 39. Books use ISBN, journals use ISSN. Mail uses USPS Intelligent Mail or the older POSTNET. Event tickets and boarding passes use Aztec or PDF417. Marketing links use QR Code. Small parts and PCBs use Data Matrix or DotCode.
What is a check digit, and do I have to type it?
It is an extra digit calculated from the others so a scanner can catch a misread. For EAN-13, EAN-8 and UPC-A this tool does the maths locally: enter the 12-, 7- or 11-digit body and it appends the correct check digit for you, or paste the full code and it verifies the last digit and tells you the expected value if it is wrong.
Why won't my printed barcode scan?
Usually the quiet zone — the blank margin each side of the symbol. Without it a scanner cannot find where the code starts and stops. Other common causes are printing too small, low contrast (always dark bars on a light background), and ink spread or blur from a low-resolution print. Keep the quiet-zone toggle on and test the real print at the real size before ordering in bulk.
What is a quiet zone?
The clear margin before the first bar and after the last one — for 1-D codes roughly ten times the width of the narrowest bar; for QR at least four modules. The quiet-zone toggle adds a standards-friendly margin around the symbol. Leave it on unless you are compositing the code into your own artwork and will add the margin yourself.
PNG or SVG — which should I download?
PNG is a fixed-resolution image: fine for screens and office documents, and for print if you download at a large scale. SVG is vector — infinitely sharp at any size and editable in Illustrator or Inkscape — so it is the better choice for packaging artwork and professional print.
GS1-128 vs plain Code 128 — what is the difference?
The bar patterns are identical. GS1-128 wraps your data in GS1 Application Identifiers such as (01) for the GTIN and (10) for a batch number, with an FNC1 marker so scanners know the data is structured GS1. Use GS1-128 when a trading partner asks for AIs; use plain Code 128 for free-form internal data.
Can I make an ISBN or ISSN barcode?
Yes. Enter the ISBN with its dashes, e.g. 978-0-262-03384-8, and the tool renders the Bookland EAN. ISSN takes the eight-digit number, e.g. 0317-8471.
Is my data private?
Yes. The barcode is rendered entirely in your browser by a library that loads on first use and stays on your device. Nothing you type is sent to a server.

Last reviewed: September 2026. Figures and formulas are checked against their published sources; see the site's data notes.