Code 11 is a numeric 1D barcode that encodes the digits 0 to 9 and the dash, developed by Intermec in 1977 and used mainly to label telecommunications equipment. barKoder reads Code 11 and checks its C and K check digits with the cameras in your iOS, Android and web apps.
| Type | Linear (1D), discrete, numeric symbology. Also known as USD-8. |
| Character set | The digits 0 to 9 and the dash (-), the 11 data characters that give Code 11 its name, plus a start/stop character |
| Capacity | Variable length. The symbology sets no fixed maximum, and labels usually carry short identifiers. |
| Check digits | C: the weighted sum of the data, with weights 1 to 10 from the right, modulo 11. K: the same over the data plus C, with weights 1 to 9, modulo 11. Short messages (about 10 characters or fewer) use C only; longer ones use C and K. |
| Standard | Developed by Intermec in 1977. There is no ISO/IEC symbology standard; encoders and readers follow the original Intermec definition. |
| Typical uses | Labeling telecommunications equipment and components |
Code 11 was developed by Intermec in 1977 to track small telephone components. It stores numbers, with the dash as the only other character, in a short and dense bar pattern.
A Code 11 symbol has five parts:
Code 11 is not self-checking. A single misread bar can turn one valid character into another, so the check digits are what catch a bad read. Readers can be set to expect no check digit, one (C) or two (C and K). With barKoder, use no check or the single (C) setting, which validates C and removes it from the result.
The dash counts as the value 10. Both check digits are calculated modulo 11, so a result of 10 is printed as a dash. Here is the calculation for the data 123-45.
| Step | Calculation | Result |
|---|---|---|
| C check digit | Weights 1 to 10 from the right (restart at 1 after 10): 5×1 + 4×2 + 10×3 + 3×4 + 2×5 + 1×6 = 71. 71 modulo 11 = 5. | C = 5 |
| K check digit | Add C to the data (123-455) and use weights 1 to 9 from the right: 5×1 + 5×2 + 4×3 + 10×4 + 3×5 + 2×6 + 1×7 = 101. 101 modulo 11 = 2. | K = 2 |
| Encoded data | Data, then C, then K, between the start and stop characters | 123-4552 |
Code 11 is a niche code. You will rarely meet it at a retail checkout, but it is still printed on telecom hardware, and that hardware passes through factories, stores and service depots.
Code 11 was built for telecommunications, and labeling telecom equipment is still its main use. Its short, dense pattern fits on small components and the edges of boards and modules.
Barcode scanning for manufacturing →Labeled telecom equipment and spare parts are received, counted and picked like any other stock. A phone app that reads Code 11 next to the EAN, Code 128 and QR codes on the same shelves saves a second device.
Barcode scanning for warehousing →Equipment is shipped to sites, returned and sent for repair. Scanning the Code 11 label at each handover keeps the item's history tied to the right number, and the check digits stop a misread from creating a wrong record.
Barcode scanning for logistics →The barKoder Barcode Scanner SDK reads Code 11 on iOS, Android, the web, Windows and Linux, and in Flutter, React Native, .NET MAUI, Capacitor, Cordova and NativeScript apps. These features matter most for this code.
Set the Code 11 checksum type to match your labels: disabled, or single (C). The setting is available in every SDK, from the Web SDK to Android, iOS and the cross-platform plugins.
Web SDK API reference →Reads supported 1D barcodes with strong deformation, where no straight line crosses all the bars, such as labels on curved or uneven surfaces. It is off by default and turned on in the SDK settings.
Segment Decoding® →Decodes several barcodes in a single camera view, whatever their type or size. Use it to count a shelf of labeled equipment in one pass.
Batch MultiScan →barKoder's free online generator creates Code 11 barcodes from any numeric input with check digits, so you can print test labels before your real ones arrive.
Free barcode generator →Enable only the decoders you need. In the Web SDK, Code 11 is Barkoder.constants.Decoders.Code11, and the checksum type is set separately.
Barkoder.setEnabledDecoders(Barkoder.constants.Decoders.Code11);
Barkoder.setCode11ChecksumType(Barkoder.constants.Code11ChecksumType.single);The checksum type takes disabled, single or double. Use single when your labels carry a C check digit, or disabled to read the data with its check digits included.
The Code 11 checksum setting on other platforms: Android, iOS, Flutter, React Native, Capacitor, Cordova, .NET MAUI, NativeScript and Python.
Install the free barKoder demo app, or open the web demo, and scan your own Code 11 labels before you integrate the SDK.
iPhone and iPad
Scan with your camera, or point it at the QR code to open the App Store.
Android phones and tablets
Scan with your camera, or point it at the QR code to open Google Play.
Any modern browser
Runs the Web SDK in your browser, on desktop or mobile, with nothing to install.
Test with known samples. Print or display the testing sheet and scan each 1D and 2D barcode with the demo app. The data sheet summarizes the SDK for your team. Need a Code 11 sample of your own? Make one with the free barcode generator.
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Code 11 is a numeric 1D barcode developed by Intermec in 1977 and used mainly to label telecommunications equipment. The name comes from its character set: the ten digits 0 to 9 plus the dash make 11 data characters. It is also known as USD-8.
No. Code 11 is a symbology, a way of drawing characters as bars, and it can hold any number of digits. An 11-digit product number is a different thing. In retail, the 11 data digits of a UPC-A code are followed by a check digit, and they are printed as a UPC-A barcode. See the EAN and UPC barcode page for those.
C is the sum of each data character times a weight from 1 to 10, counted from the right, modulo 11. K is calculated the same way over the data plus C, with weights from 1 to 9. The dash counts as 10, and a result of 10 is printed as a dash. Short messages use C only; longer ones use C and K. In barKoder you set the expected checksum type to disabled, single or double.
Use the free barKoder barcode generator. Choose Code 11, type your number and download the image. The generator adds the check digits for you. Print a few labels to test your scanning app before your real labels arrive.
Yes, if the scanning app includes a Code 11 decoder. Code 11 is rarely found on retail scanners, so check that your decoder supports it. The barKoder SDK reads Code 11 with the camera on iOS and Android phones and in web apps through the WASM Barcode Scanner SDK. Try it in the free demo app first, then enable Barkoder.constants.Decoders.Code11 in your own app.
Test the SDK on your own equipment labels with a free 30-day trial, or talk to an SDK expert about your project.
