Barcode Generator

Make EAN, UPC, Code 128 and ISBN barcodes with correct check digits, one at a time or as a printable label sheet.

Barcode type

Stock, asset and shipping labels: letters, digits and symbols.

Make

Text

Design

X-dimension (mm)

The narrowest bar. Default 0.33 mm.

Bar height (mm)

Default 15 mm, text not included.

Text under the bars

Bars

Background

Your barcode appears here as you type.

PNG resolution

The PNG's X is 0.339 mm, 4 whole dots at 300 dpi, so it prints 2.6% larger than the PDF and SVG.

Makes barcodes for products, cartons, books and stock: EAN-13, EAN-8, UPC-A, UPC-E, ITF-14, GS1-128, ISBN, Code 128 and Code 39. It adds a missing check digit or says which digit is wrong, sizes the bars by the GS1 tables for where the code will be scanned, and reads each barcode back with a test reader. Make one, or up to 1,000 from a list or a sequence as a ZIP of images or an A4 label sheet. Everything happens in your browser: the values never leave your device.

Which barcode to use

Products sold in shops — EAN-13 worldwide, UPC-A in the United States and Canada; EAN-8 and UPC-E where a pack has no room. The number comes from GS1 (below).
Outer cases and cartons — ITF-14, printed with the bearer bars around it, or GS1-128.
Pallets and shipments — GS1-128, whose application identifiers in brackets carry a GTIN (01), batch (10), best-before date (15) or shipping container code (00). The encoder checks every element against GS1's rules, so a bad date or check digit is named.
Books — ISBN, entered as ISBN-10 or ISBN-13, printed as an EAN-13 with the ISBN line above it and an optional 5-digit price add-on.
Your own stock, assets and labels — Code 128, which holds letters, digits, symbols and Western European accented letters. Code 39 holds only capitals, digits and - . $ / + % and space, for older systems that expect it.

Scanned at picks the GS1 table the sizes come from. The X-dimension is the width of the narrowest bar; every other bar and space is a whole number of X wide. It starts at the table's target, and the bar height at the table's minimum for that X. Outside the table's range the tool warns but still makes the code, since it can't know every use. Quiet zones, the blank margins a scanner needs, are always added.

The PDF and SVG print at the exact X-dimension. A PNG is made for a printer resolution (203, 300, 600 dpi), with each X a whole number of dots so every bar edge is sharp, and that resolution written into the file. Whole dots can't always hit the X exactly, so the tool rounds toward the GS1 range: at 300 dpi, 0.264 mm becomes 4 dots (0.339 mm) rather than dropping below the minimum. Print at 100%, not “Fit to page”, or the printer rescales it.

Many barcodes takes values one per line, or a start, count and step. A tab splits a line into value and label, as two spreadsheet columns paste; the label prints under the code on a label sheet and names its file in the ZIP. Commas are part of the value. Lines that can't be encoded are listed by number and the rest still generate. A sequence keeps leading zeros and gives each barcode its own check digit. A4 label sheets come with 21, 24, 40, 65 labels each, sized from Avery's templates, or any custom grid; each code prints at its true size, so a code too large for the label is reported rather than shrunk.

The colours must be dark bars on a light background. Most scanners read by red light, so the tool also warns about red or orange bars, which a red light can't tell from white.

How the check digit is worked out

EAN, UPC, ITF-14 and every GTIN end in a check digit that lets a scanner catch a misread. Starting from the digit next to the check digit and moving left, the digits are multiplied by 3, 1, 3, 1 and so on, and added up. The check digit is what brings that sum up to the next multiple of 10. One wrong digit, or most swaps of two neighbours, changes the sum, so the check fails.

ISBN-10 used a different check, modulo 11, whose check character can be X for 10. Converting to ISBN-13 puts 978 in front of the first nine digits and works out a new check digit the GS1 way. UPC-E is a UPC-A number with its zeros squeezed out; its check digit is the full UPC-A number's.

sum = 3 × (1st, 3rd, 5th … digit from the right) + 1 × (2nd, 4th … digit from the right)

check digit = (10 − sum mod 10) mod 10

Examples

An EAN-13 check digit

Number: 590123412345
Weights: 1 3 1 3 1 3 1 3 1 3 1 3
Products: 5 + 27 + 0 + 3 + 2 + 9 + 4 + 3 + 2 + 9 + 4 + 15
Sum: 83
Barcode number: 5901234123457

83 needs 7 to reach the next multiple of 10, so the check digit is 7. Type the 12 digits and the tool adds it; type all 13 with another last digit and it says which digit it should be.

An ISBN-10 as a book barcode

ISBN: 0-306-40615-2
Barcode number: 9780306406157

The ISBN-10 check digit 2 is checked first, then dropped: 978 goes in front of the other nine digits and a new GS1 check digit goes on the end.

A UPC-E number and the UPC-A it stands for

Barcode type: UPC-E
Number: 0123456
Barcode number: 01234565
As UPC-A: 012345000065

The last of the six digits says how the zeros were removed: from 5 to 9, it is the product number's last digit, after four zeros that were taken out. Many scanners report the UPC-A form, which is why a UPC-E barcode often reads back as 12 or 13 digits.

GS1 print sizes

X-dimension range, minimum bar height and quiet zones, from the GS1 General Specifications (Release 26.0)

Barcode	Scanned at	X min (mm)	X target (mm)	X max (mm)	Min height at target X (mm)	Quiet zones (left / right)
EAN-13	Shop checkout (table 1)	0.264	0.330	0.660	22.85	11X / 7X
EAN-13	Shop checkout and warehouses (table 3)	0.495	0.660	0.660	45.70	11X / 7X
EAN-13	Warehouses only (outer cases) (table 2)	0.495	0.660	0.660	45.70	11X / 7X
UPC-A	Shop checkout (table 1)	0.264	0.330	0.660	22.85	9X / 9X
UPC-A	Shop checkout and warehouses (table 3)	0.495	0.660	0.660	45.70	9X / 9X
UPC-A	Warehouses only (outer cases) (table 2)	0.495	0.660	0.660	45.70	9X / 9X
UPC-E	Shop checkout (table 1)	0.264	0.330	0.660	22.85	9X / 7X
UPC-E	Shop checkout and warehouses (table 3)	0.495	0.660	0.660	45.70	9X / 7X
UPC-E	Warehouses only (outer cases) (table 2)	0.495	0.660	0.660	45.70	9X / 7X
EAN-8	Shop checkout (table 1)	0.264	0.330	0.660	18.23	7X / 7X
EAN-8	Shop checkout and warehouses (table 3)	0.495	0.660	0.660	36.46	7X / 7X
ITF-14	Warehouses only (outer cases) (table 2)	0.495	0.495	1.016	31.75	10X / 10X, inside the bearer bars
GS1-128	Warehouses only (outer cases) (table 2)	0.495	0.495	1.016	31.75	10X / 10X
GS1-128	Pallets and shipments (logistic units) (table 5)	0.495	0.495	0.940	31.75	10X / 10X

Where the numbers and sizes come from

The sizes are copied from the symbol specification tables of the GS1 General Specifications, §5.12.3: table 1 (Table 5-44) for trade items scanned in general retail POS and not general distribution; table 3 (Table 5-48) for trade items scanned at general retail POS and general distribution; table 2 (Table 5-47) for trade items scanned in general distribution only; table 5 (Table 5-51) for logistic units scanned in general distribution. Heights exclude the text under the bars, and for EAN and UPC they scale with X between the figures the tables give. An add-on sits 9X after its main symbol, within the 7X to 12X the tables allow, and ends with a 5X quiet zone. Healthcare tables are not offered.

A barcode number for trade is unique only when it comes from GS1: a business joins its national GS1 organisation and is given a GS1 Company Prefix, from which it numbers its products. GS1 Australia warns that numbers bought from resellers are no longer managed by GS1, so there is no guarantee they stay unique. In India, GS1 India is the only authorised provider of numbers starting with 890. The tool checks that a number's check digit is correct; it can't check that the number was issued to you.

Sources

GS1 General Specifications, Release 26.0 (January 2026), §5.12.3 — GS1
How to obtain a GS1 Company Prefix? — GS1
Barcode Standards FAQs — GS1 Australia
Get a barcode — GS1 India

Reviewed 15 October 2026

Frequently asked questions

Not for your own stock, assets or shelf labels: any Code 128 or Code 39 value works inside your business. To sell through shops or online marketplaces, the EAN or UPC number must be one issued to you through GS1. The barcode image itself costs nothing; this tool makes it from the number.

For shop checkout, GS1 allows an EAN-13 X-dimension down to 0.264 mm, with bars at least 18.28 mm high at that size. Smaller codes scan less reliably, and bars should never be cut shorter to fit a pack. Keep the quiet zones clear of other print.

Usually it is the same number in another form. Many scanners report UPC-A as 13 digits with a leading 0, UPC-E as the UPC-A number it stands for, and a Code 39 check character as part of the text unless set to drop it. Scanners can also be set to leave out the check digit or add-on. If the digits truly differ, the code was printed too small, too faint or without its quiet zones.

Yes, with no licence or fee. DENSO WAVE, which invented the QR code, states that it can be used freely as long as it follows the JIS or ISO standards. "QR Code" is a registered trademark of DENSO WAVE INCORPORATED in Japan and other countries.