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JavaScript MRZ Scanner UI Components - SDK Features

The MRZ (Machine Readable Zone) Scanner is able to scan and decode the MRZ data on an ID card or passport.

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Integrating the MRZ Scanner UI


ScanbotSDK MRZ Scanner takes an instance of MrzScannerConfiguration as its argument. This is your main object for configuration options, styling and receiving the results.

MrzScannerConfiguration inherits the base properties:

  • containerId – The id of the containing HTML element where the MRZ Scanner will be initialized. Required
  • videoConstraints – The desired video resolution. Optional, defaults to 1920x1080
  • mirrored - Whether the screen should be mirrored. Useful when using a user-facing camera. false by default
  • preferredCamera - Camera label or camera device id. If not available, a default camera is used as fallback
  • onError – Callback when something went wrong. Optional

Additionally, ScanbotSDK MRZ Scanner has the following configurable options:

  • onMrzDetected – Your callback for receiving detection results. Required
  • accumulatedFrameVerificationConfiguration – Configures when a scan result should be considered verified, i.e. when it's verificationSuccessful property will be true. Optional. Should be set to an object with the following properties:
    • maximumNumberOfAccumulatedFrames: number – Maximum number of accumulated frames to inspect to verify a scan result. 3 by default.
    • minimumNumberOfRequiredFramesWithEqualRecognitionResult: number – Minimum number of accumulated frames that have an equal result. 2 by default.

The result of onMrzDetected is a MrzResult object that contains the following properties:

documentNumber?: MrzField;
issuingAuthority?: MrzField;
departmentOfIssuance?: MrzField;
givenNames?: MrzField;
surname?: MrzField;
nationality?: MrzField;
birthDate?: MrzField;
gender?: MrzField;
expiryDate?: MrzField;
personalNumber?: MrzField;
travelDocType?: MrzField;
travelDocTypeVariant?: MrzField;
optional1?: MrzField;
optional2?: MrzField;
discreetIssuingStateOrOrganization?: MrzField;
kindOfDocumentField?: MrzField;
documentType?: MrzField;
format?: MrzField;
pinCode?: MrzField;
languageCode?: MrzField;
versionNumber?: MrzField;
checkDigits?: MrzCheckDigits;
verificationSuccessful?: boolean;

MrzCheckDigits contains values of various check digit types as follows:

general?: MrzField;
documentNumber?: MrzField;
birthDate?: MrzField;
expiryDate?: MrzField;
personalNumber?: MrzField;

MrzField contains the following fields:

name?: string;
value?: string;
confidence?: number;
validated?: MRZFieldValidationStatus;

MRZFieldValidationStatus is a custom type:

type MRZFieldValidationStatus =
| 'Failure'
| 'NotValidated';


ScanbotSDK MRZ Scanner has the following style options and their default values:

style?: {
window: {
aspectRatio: 4,
widthProportion: 0.8,
borderColor: "white",
left: "50%",
top: "50%",
transform: "translate(-50%, -50%)"
text: {
color: string = "white";
size: string = "0.9em";
weight: number = 300;
hint: "Please align the code in the frame above to scan it"
backgroundColor: string = "rgba(0, 0, 0, 0.7)";

window element is used to configure the viewfinder. It uses the WindowStyleConfiguration interface that has the following attributes:

width?: string;
height?: string;
aspectRatio?: number;
widthProportion?: number;
borderColor?: string;
left?: string;
top?: string;
transform?: string;

width and height elements can be used for configuring the size of the viewfinder in pixels. However, aspectRatio and widthProportion elements can be used for configuring the size of the viewfinder in a more responsive way. aspectRatio specifies the aspect ratio as width/height. widthProportion specifies the proportional length of the viewfinder. (1 means full length of the visible area of the scanner.)

To change a specific style, simply assign it another value, e.g: = { window: { borderColor: "pink" } };

Default style configuration:

const WindowStyle: WindowStyleConfiguration = {
aspectRatio: 4,
widthProportion: 0.8,
borderColor: "white",
left: "50%",
top: "50%",
transform: "translate(-50%, -50%)"
const TextStyle: TextStyleConfiguration = {
color: "white",
size: "0.9em",
weight: 300,

const MrzScannerStyle: ViewFinderConfiguration = {
window: WindowStyle,
text: TextStyle,
backgroundColor: "rgba(0, 0, 0, 0.7)",
hint: "Please hold the device over the MRZ code to start scanning"

Opening the Scanner

To open the MRZ Scanner, simply call the relevant SDK function with the configuration object:

const config = {
onMrzDetected: onMrzDetected,
onError: onError

const scanner = await scanbotSDK.createMrzScanner(configuration);

You should store the MRZ Scanner object in a globally accessible location, as additional MRZ Scanner actions are functions of that object.


To handle MRZ results (avoid duplicate scans etc), ScanbotSDK offers the following convenient methods to pause and resume detection while you are processing the data on your side:

resumeDetection(): void;
pauseDetection(): void;
isDetectionPaused(): boolean;

Switching between the front and rear camera

swapCameraFacing(force?: boolean): void;

swapCameraFacing(true) indicates that only the swapped camera (e.g. front camera) is acceptable; if the swapped camera is not available, or the user declines the permission to use that camera, the media request will fail.


Firefox on Android: Due to current Firefox browser limitations, we highly recommend checking the running browser and disabling this feature for Firebox browsers.

Switching to a specific available camera

fetchAvailableCameras(): Promise<CameraInfo[]>;
switchCamera(deviceId: string, mirrored?: boolean): void;
getActiveCameraInfo(): CameraInfo | undefined;
interface CameraInfo {
deviceId: string;
label: string;
facingMode?: CameraFacingMode;
supportsTorchControl?: boolean;

type CameraFacingMode = 'front' | 'back' | 'unknown';

You can search for available cameras on the running browser by using fetchAvailableCameras method of a scanner. You can retrieve the label, device id and the camera facing mode information of the active camera of a scanner by using getActiveCameraInfo method. And, you can switch to another available camera by utilizing its device id, by using switchCamera method.

const cameras = await scanner.fetchAvailableCameras()
if (cameras) {
const currentCameraInfo = scanner.getActiveCameraInfo();
if (currentCameraInfo) {
const cameraIndex = cameras.findIndex((cameraInfo) => { return cameraInfo.deviceId == currentCameraInfo.deviceId });
const newCameraIndex = (cameraIndex + 1) % (cameras.length);


Controlling the torch (flashlight)

On some mobile devices, the browser can control the torch (flashlight). Check scanner.getActiveCameraInfo().supportsTorchControl to see if the browser can control the torch for the currently active camera. If true, you can control the torch by using the setTorchState method of the scanner.

setTorchState(state: boolean): Promise<void>;

On Android devices, only Chrome supports torch control. Starting with iOS 17.4, all supported browsers on iOS offer torch control functionality.


As with the Document Scanner, the MRZ Scanner should also be properly disposed of when you have detected and processed the relevant MRZ:

await mrzScanner.dispose();

Detection on the Image

async createSimpleMRZRecognizer(): Promise<SimpleMrzRecognizer>

Example usage:


reader.onload = async (e) => {

const recognizer = await scanbotSDK.createSimpleMRZRecognizer();

const result = await recognizer.recognizeURL(reader.result);


await recognizer.release();

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