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FAQ and Licensing

  • 1. Per Barcode Scan:

    A barcode scan means a unique barcode value (of the same symbology) decoded from an image or a video frame.

    Some examples for your reference:

    Examples Count of barcode scan
    Two duplicated barcodes on an image 1
    Two different barcodes on an image 2
    continuous scanning (video mode) of one barcode * 1
    Two barcodes with the same encoded text but different symbologies 2

    Scan Duplicates in Video Stream Mode using the Class BarcodeScanner:

    Developers can specify a time frame (duplicateForgetTime, default to 3 seconds) to filter out duplicates.

    A scan duplicate is when a barcode result reads the same value as a previously scanned barcode within duplicateForgetTime, say, 3 seconds. Once a scan is duplicated, the [time stamp] refreshes to the time when the latest duplicate was read. Each barcode result has its independent life cycle that begins when it is first scanned and refreshes when a duplicate is scanned.

  • 2. Per Device:

    For each device, a random number is generated and mapped into a UUID-compatible string (also referred to as a UUID here), which is used to uniquely identify the device.

    NOTE: Because of the way a UUID is generated and stored, a "device" here is essentially a browser accessing a specific domain which means if multiple browsers are used on the same hardware or a browser is accessing multiple domains that are all using the library with the same key, they are counted separately as multiple "devices". Another thing is that this UUID could be lost if the browser's indexedDB store gets deleted. If this happens (like when the browser data is cleared or the indexedDB is deleted manually), a different UUID will be regenerated in order to use the library and as a result, the "device" will be counted as a new one.

  • 3. Per Concurrent Device:

    Per Concurrent Device: Unlike "Per Device" which counts all devices that have used the library, this option counts how many unique devices are using the library in each 3-minute time frame. To make it clearer, each day is divided into 480 slots of 3-minute-long windows. The device count is a sum of unique devices using the library in the 3-minute window. The license continues to work if the count stays below the authorized concurrent device limit.

  • 4. How do I activate the licenses?
    • Initial Order: A manual activation is required.
    • Increase Quota: Auto activation on the day of purchase. The credits will be added up to the quota of the old key.
    • Renewal: Auto activation at the beginning of next period. The key remains unchanged so there is no need to update your code.
  • 5. Will the license of a barcode scan package expire?
    • Initial Order: The credits expire one year after license activation.
    • Increase Quota: If you purchase a package to increase quota, the expiration of the new credits will be aligned to the current expiration date, i.e. all credits expire at the end of the current period.
    • Renewal: If you purchase a renewal, the new credits will be activated at the very beginning of the new period, and expires one year after the current expiration date.
  • 6. How do I increase my barcode scan quota?

    To increase the quota of your license, please send your request along with your current key to  sales@dynamsoft.com. For your convenience, you key will remain unchanged after the extension.

  • 7. Will the unused credits be rolled over to the next period?


  • 8. Can I filter unwanted barcodes to reduce the consumption of my license?

    Yes. There are many pre-scanning settings you can apply to your barcode scanner.

    For example, you can specify barcode format, limit the scanning to predefined regions or return only high-confidence values. For more settings, please refer to  this page.

  • 9. Is an internet connection required to scan barcodes?

    Yes. An internet connection is required on the first visit to the barcode scanner page on the client side. Afterward, the barcode scanner can work completely offline for a maximum of 7 days.

  • 10. For an environment with no internet connection allowed, can I use your barcode reader SDK?

    Yes. For enterprise customers who do not allow any internet connection to the Dynamsoft's license server, we offer a few flexible options. Please submit your requirement via  this form for a custom licensing model.

  • 11. How secure is the license verification mechanism?

    We've implemented the following for security purpose.

    • 1. Domain binding is enforced to make sure your license only works on your website
    • 2. The library sends no customer data except for the count and type of barcode scans to the license server
    • 3. The library generates a random number and map that to be a UUID-compatible string which is used to uniquely identify a device. Check out more details in Question 2 above