🪪 Thai National ID Card OCR

🪪 บัตรประชาชนไทย

Welcome to Thai National ID Card OCR API, version 3.5, an AI product developed by iApp Technology Co., Ltd. Our API is designed to extract text information from both the front and back face of Thai National ID card images with high accuracy and speed. Our API supports JPEG, JPG, PNG, HEIC, HEIF, and PDF file formats and can process an ID card image in 1-2 seconds.

Try Demo

Visit our API Portal to test the Thai National ID Card OCR API with your own images.

Getting Started

Prerequisites
- An API key from iApp Technology
- Thai national ID card images (front/back)
- Supported file formats: JPEG, JPG, PNG, HEIC, HEIF, PDF
- Maximum file size: 10MB
Quick Start
- Fast processing (1-2 seconds per card)
- High accuracy text extraction (98.13% at character level)
- Support for multiple file formats
Key Features
- Detailed field extraction including:
  - ID number
  - Full name (Thai and English)
  - Date of birth
  - Religion
  - Address
  - Issue and expiry dates
- Support for both front and back of ID cards
- Option to return original OCR text and processed images
- Flexible JSON response format
Security & Compliance
- GDPR and PDPA compliant
- No data retention after processing

How to get API Key?

Please visit API Portal to view your existing API key or request a new one.

Example

Front side

Request:

curl -X POST https://api.iapp.co.th/thai-national-id-card/v3.5/front
    -H "apikey: YOUR_API_KEY"
    -F "file=@/path/to/idcard.jpg"

Response:

{
    "address": "XXXXXX XXXX X ต.หนองปรือ อ.บางละมุง จ.ชลบุรี",
    "alley": "",
    "detection_score": 0.981011797984441,
    "district": "บางละมุง",
    "en_dob": "XX Mar 1957",
    "en_expire": "XX Mar 2025",
    "en_fname": "XXXXXX",
    "en_init": "Mrs.",
    "en_issue": "26 Jul 2016",
    "en_lname": "Lopez",
    "en_name": "Mrs. XXXXXX Lopez",
    "error_message": "",
    "face": "/9j/4AAQ...UAFFFFAH/9k=", # Base64 of photo's image
    "gender": "Female",
    "home_address": "XXXXX XXX",
    "house_no": "XXXXXX",
    "id_number": "34117XXXXXX334",
    "id_number_status": 1,
    "lane": "",
    "postal_code": "20150", # Automatic Retrieve from Database
    "process_time": 1.3018648624420166, # Seconds
    "province": "ชลบุรี",
    "religion": "",
    "request_id": null,
    "road": "",
    "sub_district": "หนองปรือ",
    "th_dob": "XX มี.ค. 2500",
    "th_expire": "XX มี.ค. 2568",
    "th_fname": "XXXXX",
    "th_init": "นาง",
    "th_issue": "XX ก.ค. 2559",
    "th_lname": "โลเปซ",
    "th_name": "นาง XXXXX โลเปซ",
    "village": "",
    "village_no": "7"
}

Backside

Request:

curl --location --request POST 'https://api.iapp.co.th/thai-national-id-card/v3.5/back' \
    --header 'apikey: {Your API Key}' \
    --form 'file=@"path/to/id-card-back.jpg"'

Response:

{
    "back_number": "JT0-XXXXXXX-05",
    "detection_score": 0.99846746524175,
    "process_time": 1.370201416015625
}

Features & Capabilities

Core Features

High accuracy text extraction (98.13% character-level accuracy)
Fast processing time (1-3 seconds per card)
Support for multiple file formats (JPEG, JPG, PNG, HEIC, HEIF, PDF)
Automatic card cropping and rotation
Return bounding boxes and scores for fields
Return base64 images of card and fields
Return raw OCR text
Support for back card side without chip

Supported Fields

Front Side

Field	Type	Description
address	String	Address on the ID card
detection_score	float	Detection score of a related field
district	String	District name on the ID card
en_dob	String	Date of birth, in English
en_expire	String	Date of expiry, in English
en_fname	String	English given name
en_init	String	Name title, in English
en_issue	String	Date of issue, in Thai
en_lname	String	English surname
en_name	String	English given name and surname
error_message	String	Error message
face	String	Base64 character string converted from the image
gender	String	Gender
home_address	String	Home address on the ID card
id_number	String	National ID number
postal_code	String	Postal Code
process_time	String	Processing time (Sec.)
province	String	Province name on the ID card
religion	String	Religion on the ID card
sub_district	String	Sub district name on the ID card
th_dob	String	Date of birth, in Thai
th_expire	String	Date of expiry, in Thai
th_fname	String	Thai given name
th_init	String	Name title, in English
th_issue	String	Date of issue
th_lname	String	Thai surname
th_name	String	Thai given name and surname

Back side

Field	Type	Description
back_number	String	Laser number on back of ID card

Common Response Fields

Field	Type	Description
detection_score	Float	Confidence score (0-1)
error_message	String	Error message if request fails
process_time	Float	Processing time in seconds

API Reference

Recognizing Thai National ID Card

This endpoint processes Thai national ID card images and returns the extracted data in a structured format.

Front Side

POST https://api.iapp.co.th/thai-national-id-card/v3.5/front

Request Headers

Name	Type	Required	Description
apikey	string	Yes	Your API key

Request Body (multipart/form-data)

Parameter	Type	Required	Description
file	File	Yes	The binary data of the image (front side)
fields	String	No	Option to choose fields in output
options	String	No	Option to choose processing tools and settings

Back Side

POST https://api.iapp.co.th/thai-national-id-card/v3.5/back

Request Headers

Name	Type	Required	Description
apikey	string	Yes	Your API key

Request Body (multipart/form-data)

Parameter	Type	Required	Description
file	File	Yes	The binary data of the image (back side)
options	String	No	Option to choose processing tools and settings

Available Options

not_crop_card - Skip card cropping
not_rotate_card - Skip auto-rotation
get_bbox - Return bounding box coordinates
get_image - Return processed image
get_original - Return original image

Response Format for Available Options

When using the available options, the response JSON will include additional fields based on the options selected:

Response with get_bbox Option

Returns bounding box coordinates for each detected field in the format [x1, y1, x2, y2] with confidence score:

{
    "bbox": {
        "address": [
            [[119, 292, 376, 334], 0.991],
            [[75, 330, 255, 362], 0.999]
        ],
        "card": [[[0, 0, 713, 462], 0.99]],
        "en_dob": [[[370, 235, 526, 266], 0.999]],
        "face": [[[544, 218, 708, 407], 0.999]]
        // Other field coordinates...
    }
}

Response with get_image Option

Returns base64 encoded cropped images for each detected field:

{
    "image": {
        "address": ["/9j/4AAQSk...", "/9j/4AAQSk..."],
        "card": ["/9j/4AAQSk..."],
        "face": ["/9j/4AAQSk..."],
        "id_number": ["/9j/4AAQSk..."]
        // Other field images...
    }
}

Response with get_original Option

Returns the original values before the autocorrect step (which occured in the post processing step) detected from the card:

{
    "original": {
        "address": "XXXXX XXXXX X ต.หนองปรือ อ.บางละมุง จ.ชลบุรี",
        "en_dob": "XX Mar. 1957",
        "en_expire": "XX Mar. 2025",
        "th_name": "นาง XXXXXX โลเปซ"
        // Other original field values...
    }
}

The response will always include the standard fields like detection_score, error_message, and process_time regardless of options used.

Error Code

Specific Error Messages

Thai National ID Card Front Side

Status Code	Status Message	Description
420	NO_ID_CARD_FOUND	The image file is not the ID card
421	IMAGE_ERROR_UNSUPPORTED_FORMAT	The image cannot be resolved. The file format may not be supported or the file is damaged
422	INVALID_IMAGE_SIZE	The size of the uploaded image does not meet the requirement
424	PLEASE_VERIFY_ID_CARD_NUMBER	The National ID Number has 13 digits but is incorrect. Response code 424 will show when using id_check option
425	CANNOT_READ_ID_CARD_NUMBER_CLEARLY	The National ID Number has less than 13 digits. Response code 425 will show when using id_check option
426	IMAGE_ERROR_UNSUPPORTED_BLACK_WHITE_IMAGE	Used gray_check option to check black-white and gray images

Thai National ID Card Back Side

Status Code	Status Message	Description
430	NO_ID_CARD_FOUND	The image file is not the ID Card
431	IMAGE_ERROR_UNSUPPORTED_FORMAT	The image cannot be resolved. The file format may not be supported or the file is damaged
432	INVALID_IMAGE_SIZE	The size of the uploaded image does not meet the requirement
434	LASER_NUMBER_NOT_FOUND	Cannot detect the laser number on back ID Card
435	CANNOT_READ_LASER_NUMBER_CLEARLY	The laser number has less than 12 digits. Response code 435 will show when using id_check option
436	IMAGE_ERROR_UNSUPPORTED_BLACK_WHITE_IMAGE	Used gray_check option to check black-white and gray images

Common Error Messages

Status Code	Status Message	Description
404	REQUESTED_URL_NOT_FOUND	API Route not found in request
405	METHOD_NOT_ALLOWED	Method name (GET, POST) in the URL is incorrect
413	FILE_IS_TOO_LARGE: (more than 2 MB)	The file size is too large
427	LONG_TIME_TO_PROCESS	The server is processed for a long time
428	LONG_TIME_TO_REQUEST	The client is waiting in the queue for a long time
461	NO_FILE_ATTACHED	No file attached
560	SERVER_IS_BUSY: (Please try again in a few seconds.)	Server is working on many requests
563	ID_CARD_API_NOT_SUPPORT_THIS_IMAGE	The API has an error in the process

Code Examples

Python

    import requests

    url = "https://api.iapp.co.th/thai-national-id-card/v3.5/front"

    payload = {
        'options': 'get_bbox,get_image'
    }

    files = [
        ('file',('id-card.jpg',open('path/to/id-card.jpg','rb'),'image/jpeg'))
    ]

    headers = {
        'apikey': 'YOUR_API_KEY'
    }

    response = requests.request("POST", url, headers=headers, data=payload, files=files)
    print(response.json())

JavaScript

const axios = require("axios")
const FormData = require("form-data")
const fs = require("fs")

const form = new FormData()
form.append("file", fs.createReadStream("path/to/id-card.jpg"))
form.append("options", "get_bbox,get_image")

const config = {
    method: "post",
    url: "https://api.iapp.co.th/thai-national-id-card/v3.5/front",
    headers: {
        apikey: "YOUR_API_KEY",
        ...form.getHeaders(),
    },
    data: form,
}

axios(config)
    .then((response) => console.log(JSON.stringify(response.data)))
    .catch((error) => console.log(error))

PHP

    <?php
    $curl = curl_init();

    $post_data = array(
        'file'=> new CURLFile('path/to/id-card.jpg'),
        'options' => 'get_bbox,get_image'
    );

    curl_setopt_array($curl, array(
        CURLOPT_URL => 'https://api.iapp.co.th/thai-national-id-card/v3.5/front',
        CURLOPT_RETURNTRANSFER => true,
        CURLOPT_POST => true,
        CURLOPT_POSTFIELDS => $post_data,
        CURLOPT_HTTPHEADER => array(
            'apikey: YOUR_API_KEY'
        ),
    ));

    $response = curl_exec($curl);
    curl_close($curl);
    echo $response;
    ?>

Swift

    import Foundation

    let headers = [
        "apikey": "YOUR_API_KEY"
    ]

    let parameters = [
        [
            "name": "file",
            "fileName": "path/to/id-card.jpg"
        ],
        [
            "name": "options",
            "value": "get_bbox,get_image"
        ]
    ]

    let boundary = "Boundary-\(UUID().uuidString)"
    var body = ""
    var error: Error? = nil

    for param in parameters {
        if let fileName = param["fileName"] {
            let fileContent = try? String(contentsOfFile: fileName, encoding: .utf8)
            body += "--\(boundary)\r\n"
            body += "Content-Disposition:form-data; name=\"\(param["name"] ?? "")\""
            body += "; filename=\"\(fileName)\"\r\n"
            body += "Content-Type: image/jpeg\r\n\r\n"
            body += fileContent ?? ""
        } else {
            body += "--\(boundary)\r\n"
            body += "Content-Disposition:form-data; name=\"\(param["name"] ?? "")\"\r\n\r\n"
            body += param["value"] ?? ""
        }
    }

    let postData = body.data(using: .utf8)

    var request = URLRequest(url: URL(string: "https://api.iapp.co.th/thai-national-id-card/v3.5/front")!,timeoutInterval: Double.infinity)
    request.addValue("YOUR_API_KEY", forHTTPHeaderField: "apikey")
    request.httpMethod = "POST"
    request.httpBody = postData

    let task = URLSession.shared.dataTask(with: request) { data, response, error in
        guard let data = data else {
            print(String(describing: error))
            return
        }
        print(String(data: data, encoding: .utf8)!)
    }

    task.resume()

Kotlin

    import okhttp3.*
    import java.io.File

    val client = OkHttpClient()

    val mediaType = MediaType.parse("image/jpeg")
    val file = File("path/to/id-card.jpg")
    val body = MultipartBody.Builder().setType(MultipartBody.FORM)
        .addFormDataPart("file", file.name, RequestBody.create(mediaType, file))
        .addFormDataPart("options", "get_bbox,get_image")
        .build()

    val request = Request.Builder()
        .url("https://api.iapp.co.th/thai-national-id-card/v3.5/front")
        .addHeader("apikey", "YOUR_API_KEY")
        .post(body)
        .build()

    client.newCall(request).execute().use { response ->
        println(response.body()?.string())
    }

Java

    import java.io.File;
    import okhttp3.*;

    public class Main {
        public static void main(String[] args) {
            OkHttpClient client = new OkHttpClient().newBuilder().build();

            MediaType mediaType = MediaType.parse("image/jpeg");
            RequestBody body = new MultipartBody.Builder().setType(MultipartBody.FORM)
                .addFormDataPart("file", "id-card.jpg",
                    RequestBody.create(mediaType, new File("path/to/id-card.jpg")))
                .addFormDataPart("options", "get_bbox,get_image")
                .build();

            Request request = new Request.Builder()
                .url("https://api.iapp.co.th/thai-national-id-card/v3.5/front")
                .method("POST", body)
                .addHeader("apikey", "YOUR_API_KEY")
                .build();

            try {
                Response response = client.newCall(request).execute();
                System.out.println(response.body().string());
            } catch(Exception e) {
                e.printStackTrace();
            }
        }
    }

Dart

    import 'package:http/http.dart' as http;

    void main() async {
        var request = http.MultipartRequest('POST',
            Uri.parse('https://api.iapp.co.th/thai-national-id-card/v3.5/front'));

        request.files.add(await http.MultipartFile.fromPath(
            'file', 'path/to/id-card.jpg'));

        request.fields['options'] = 'get_bbox,get_image';

        request.headers.addAll({
            'apikey': 'YOUR_API_KEY'
        });

        http.StreamedResponse response = await request.send();

        if (response.statusCode == 200) {
            print(await response.stream.bytesToString());
        } else {
            print(response.reasonPhrase);
        }
    }

Limitations and Best Practices

Limitations

Maximum file size: 10MB
Supported formats: JPEG, JPG, PNG, HEIC, HEIF, PDF

Best Practices

Ensure good image quality
Check detection_score in response
Handle error messages appropriately
Validate ID card number format
Consider using options parameter for specific needs

Accuracy & Performance

Overall Accuracy

Detection score typically above 96%
Field-specific accuracy varies

Processing Speed

Average: 1-2 seconds
May vary based on image size and quality

Factors Affecting Accuracy

Image Quality
- Resolution (Minimum 300 DPS)
- Lighting
- Focus
Card Condition
- Physical damage
- Reflections
- Text clarity

History

Version	Release Date	Accuracy	Key Improvements
3.5	Nov 2022	98.13%	New OCR Engine, Faster Processing
3.4	Jul 2022	93.25%	Added Thai Military Ranks
3.1-3.3	May-Jul 2021	92.75%	Internal Beta Release
3.0	Feb 2021	91.75%	Major Accuracy Improvements
2.0	Feb 2020	85%	Added Back Card Support
1.0	Nov 2019	76%	Initial Release

Pricing

AI API Service Name	Endpoint	IC Per Request	On-Premise
Thai National ID Card OCR (v3.5)	iapp_thai_national_id_card_ocr_v3.5_back	0.75 IC/Request	Contact
Thai National ID Card OCR (v3.5)	iapp_thai_national_id_card_ocr_v3.5_front	1.25 IC/Request	Contact

Getting Started​

Example​

Front side​

Request:​

Response:​

Backside​

Request:​

Response:​

Features & Capabilities​

Core Features​

Supported Fields​

Front Side​

Back side​

Common Response Fields​

API Reference​

Recognizing Thai National ID Card​

Front Side​

Request Headers​

Request Body (multipart/form-data)​

Back Side​

Request Headers​

Request Body (multipart/form-data)​

Available Options​

Response Format for Available Options​

Response with get_bbox Option​

Response with get_image Option​

Response with get_original Option​

Error Code​

Specific Error Messages​

Thai National ID Card Front Side​

Thai National ID Card Back Side​

Common Error Messages​

Code Examples​

Python​

JavaScript​

PHP​

Swift​

Kotlin​

Java​

Dart​

Limitations and Best Practices​

Limitations​

Best Practices​

Accuracy & Performance​

Overall Accuracy​

Processing Speed​

Factors Affecting Accuracy​

History​

Pricing​

Getting Started

Example

Front side

Request:

Response:

Backside

Request:

Response:

Features & Capabilities

Core Features

Supported Fields

Front Side

Back side

Common Response Fields

API Reference

Recognizing Thai National ID Card

Front Side

Request Headers

Request Body (multipart/form-data)

Back Side

Request Headers

Request Body (multipart/form-data)

Available Options

Response Format for Available Options

Response with get_bbox Option

Response with get_image Option

Response with get_original Option

Error Code

Specific Error Messages

Thai National ID Card Front Side

Thai National ID Card Back Side

Common Error Messages

Code Examples

Python

JavaScript

PHP

Swift

Kotlin

Java

Dart

Limitations and Best Practices

Limitations

Best Practices

Accuracy & Performance

Overall Accuracy

Processing Speed

Factors Affecting Accuracy

History

Pricing