🧾 Thai Receipt OCR 🆕

🧾 ใบเสร็จรับเงิน / ใบแจ้งหนี้ / ใบวางบิล / ใบกำกับภาษี

Welcome to the Thai Receipt OCR API, an AI-powered solution developed by iApp Technology Co., Ltd. for extracting data from Thai receipts and invoices. This documentation will help you integrate and use our OCR service effectively.

Example Images (Click to try)

API Key

Demo key is limited to 10 requests per day per IP
Click here to get your API key

Endpoint URL

cURL Command

Upload Receipt

Getting Started

1. Prerequisites

   • An API key from iApp Technology
   • Thai / English receipt using printed or handwritten images
   • Supported file formats: JPEG, JPG, PNG, HEIC, HEIF, PDF
   • Maximum file size: 10MB

2. Quick Start

   • Fast processing (5-10 seconds per document)
   • High accuracy text extraction
   • Support for multiple file formats

3. Key Features

   • Detailed field extraction including:
     • Invoice details (type, ID, date, book number)
     • Issuer information (name, address, tax ID, contact)
     • Customer information (name, address, tax ID, contact)
     • Line item details (item code, name, quantity, unit price, total)
     • Financial summary (subtotal, discount, VAT, grand total)
   • Support for both single-page and multi-page documents (PDF)
   • Option to return original OCR text and processed images
   • Flexible JSON response format with detailed field extraction

4. Security & Compliance

   • GDPR and PDPA compliant
   • Secure API endpoints
   • No data retention after processing

Our API is designed to handle various receipt formats and layouts commonly used in Thailand, from simple retail receipts to formal tax invoices. The post-processing AI model is trained to understand Thai receipt structures and can reliably extract information even from noisy or poorly scanned documents.

Example

Here's a sample receipt and its extracted data:

Request:

cURL

curl -X POST "https://api.iapp.co.th/ocr/v3/receipt/file" \
-H "apikey: YOUR_API_KEY" \
-F "file=@/path/to/receipt.jpg" \
-F "return_image=false" \
-F "return_ocr=false"

How to get API Key?

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

Response:

{
    "message": "success",
    "processed": {
        "invoiceType": "ใบเสร็จรับเงิน/ใบกำกับภาษีอย่างย่อ",
        "invoiceBook": null,
        "invoiceID": "4504RC112566/004044",
        "invoiceDate": "27/11/2566",
        "issuerName": "หจก.บุญรอดคอฟฟี (ตลาดรัตนบุรี)",
        "issuerTaxID": "0323560000723",
        "items": [
            {
                "itemNo": 1,
                "itemName": "ชาเขียวนม ร้อน ขนาดใหญ่",
                "itemUnit": 1,
                "itemUnitCost": 60.0,
                "itemTotalCost": 60.0
            }
        ],
        "totalCost": 60.0,
        "discount": 0.0,
        "totalCostAfterDiscount": 60.0,
        "vat": 3.93,
        "grandTotal": 60.0
    },
    "process_ms": 6821
}

Features & Capabilities

Core Features

1. Document Processing

   • High accuracy text extraction and field recognition
   • Thai / English language supported.
   • Printed / Handwritten supported.
   • Fast processing time of 5-10 seconds per document
   • Multi-format support (JPEG, JPG, PNG, HEIC, HEIF, PDF)
   • Multi-page document handling
   • Option to return original OCR text and processed images
   • GDPR and PDPA compliant processing

2. Data Extraction

   • Flexible JSON response format with detailed field extraction

Supported Fields

Field	Type	Description
invoiceType	String	Title or type of invoice
invoiceBook	String	Book number of invoice
invoiceID	String	ID number of invoice
invoiceDate	String	Date of invoice issuance
purchaseOrderID	String	ID number of linked purchase order
issuerName	String	Name of invoice issuer
issuerAddress	String	Address of invoice issuer
issuerTaxID	String	Tax ID of invoice issuer
issuerPhone	String	Contact phone of invoice issuer
customerName	String	Name of customer
customerAddress	String	Address of customer
customerTaxID	String	Tax ID of customer
customerPhone	String	Contact phone of customer
items	Array	Array of line items with details below
- itemNo	String	Item sequence number
- itemCode	String	Product/service code
- itemName	String	Product/service name
- itemUnit	Number	Quantity of item
- itemUnitCost	Number	Cost per unit
- itemTotalCost	Number	Total cost for this item
totalCost	Number	Sum of all item costs
discount	Number	Discount amount if applicable
totalCostAfterDiscount	Number	Total cost after applying discount
vat	Number	Value Added Tax amount (7%)
grandTotal	Number	Final total amount including VAT

Note: All currency values are rounded to two decimal places.

API Reference

Welcome to the Thai Receipt OCR API, a powerful tool for converting Thai receipts and invoices into structured JSON data. This API leverages advanced OCR and AI technologies to extract key information such as invoice details, issuer and customer data, line items, and financial totals.

Recognizing Receipt

There are two endpoints available for processing receipts:

1. File Upload

POST https://api.iapp.co.th/ocr/v3/receipt/file

Request Headers

Name	Type	Required	Description
apikey	string	Yes	Your API key

Request Body (multipart/form-data)

Parameter	Type	Required	Description
file	file	Yes	Receipt image (JPEG, PNG) or PDF document
return_image	boolean	No	Include base64 encoded image in response (default: false)
return_ocr	boolean	No	Include raw OCR text in response (default: false)

Supported File Types

• Images: JPEG, PNG
• Documents: PDF (single or multiple pages)

Response Format

{
    "message": "success",
    "raw": {
        "image": "string", // Base64 encoded, only if return_image=true
        "text": "string" // Only if return_ocr=true
    },
    "processed": {
        "invoiceType": "string",
        "invoiceBook": "string",
        "invoiceID": "string",
        "invoiceDate": "string",
        "purchaseOrderID": "string",
        "issuerName": "string",
        "issuerAddress": "string",
        "issuerTaxID": "string",
        "issuerPhone": "string",
        "customerName": "string",
        "customerAddress": "string",
        "customerTaxID": "string",
        "customerPhone": "string",
        "items": [
            {
                "itemNo": "string",
                "itemCode": "string",
                "itemName": "string",
                "itemUnit": "number",
                "itemUnitCost": "number",
                "itemTotalCost": "number"
            }
        ],
        "totalCost": "number",
        "discount": "number",
        "totalCostAfterDiscount": "number",
        "vat": "number",
        "grandTotal": "number"
    },
    "template": "receipt",
    "iapp": "string",
    "process_ms": "number"
}

Error Handling

Status	Code	Description
400	BAD_REQUEST	Invalid parameters or file format
401	UNAUTHORIZED	Invalid or missing API key
404	NOT_FOUND	Invalid endpoint
500	INTERNAL_SERVER_ERROR	Processing failed

2. Base64 Image

POST https://api.iapp.co.th/ocr/v3/receipt/base64

Request Headers

Name	Type	Required	Description
apikey	string	Yes	Your API key

Request Body

You can send the base64 data either as JSON or form data:

JSON Format:

{
    "base64_string": "string", // Base64 encoded image data
    "return_image": false,     // Optional
    "return_ocr": false        // Optional
}

Form Data Format:

Parameter	Type	Required	Description
base64_string	string	Yes	Base64 encoded image data
return_image	boolean	No	Include base64 encoded image in response (default: false)
return_ocr	boolean	No	Include raw OCR text in response (default: false)

Response Format

Same as file upload endpoint

Code Examples

Python (File Upload)

import requests
apiKey = 'YOUR_API_KEY'
filePath = '/path/to/receipt.jpg'
url = "https://api.iapp.co.th/ocr/v3/receipt/file"

headers = {'apikey': apiKey}
files = {'file': ('receipt.jpg', open(filePath, 'rb'), 'image/jpeg')}
data = {'return_image': 'false', 'return_ocr': 'false'}

response = requests.post(url, headers=headers, files=files, data=data)
print(response.json())

Python (Base64)

import requests
import base64

apiKey = 'YOUR_API_KEY'
url = "https://api.iapp.co.th/ocr/v3/receipt/base64"

# Read image file and convert to base64
with open('/path/to/receipt.jpg', 'rb') as image_file:
    base64_string = base64.b64encode(image_file.read()).decode()

headers = {
    'apikey': apiKey,
    'Content-Type': 'application/json'
}

data = {
    'base64_string': base64_string,
    'return_image': False,
    'return_ocr': False
}

response = requests.post(url, headers=headers, json=data)
print(response.json())

Javascript (File Upload)

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

const apiKey = "YOUR_API_KEY"
const filePath = "/path/to/receipt.jpg"
const url = "https://api.iapp.co.th/ocr/v3/receipt/file"

const form = new FormData()
form.append("file", fs.createReadStream(filePath))
form.append("return_image", "false")
form.append("return_ocr", "false")

try {
    const response = await axios.post(url, form, {
        headers: {
            ...form.getHeaders(),
            apikey: apiKey,
        },
    })
    return response.data
} catch (error) {
    throw error
}

Javascript (Base64)

const axios = require("axios")
const fs = require("fs")

const apiKey = "YOUR_API_KEY"
const url = "https://api.iapp.co.th/ocr/v3/receipt/base64"

// Read image file and convert to base64
const base64String = fs.readFileSync('/path/to/receipt.jpg', {encoding: 'base64'})

const data = {
    base64_string: base64String,
    return_image: false,
    return_ocr: false
}

try {
    const response = await axios.post(url, data, {
        headers: {
            'Content-Type': 'application/json',
            'apikey': apiKey
        }
    })
    return response.data
} catch (error) {
    throw error
}

PHP (File Upload)

$url = 'https://api.iapp.co.th/ocr/v3/receipt/file';
$apiKey = 'YOUR_API_KEY';
$filePath = '/path/to/receipt.jpg';

$headers = array(
    'apikey: ' . $apiKey
);

$postFields = array(
    'file' => new CURLFile($filePath),
    'return_image' => 'false',
    'return_ocr' => 'false'
);

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, $postFields);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);

$response = curl_exec($ch);
curl_close($ch);

echo $response;

PHP (Base64)

<?php
$url = 'https://api.iapp.co.th/ocr/v3/receipt/base64';
$apiKey = 'YOUR_API_KEY';
$filePath = '/path/to/receipt.jpg';

// Read image file and convert to base64
$base64String = base64_encode(file_get_contents($filePath));

$data = array(
    'base64_string' => $base64String,
    'return_image' => false,
    'return_ocr' => false
);

$headers = array(
    'Content-Type: application/json',
    'apikey: ' . $apiKey
);

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($data));
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);

$response = curl_exec($ch);
curl_close($ch);

echo $response;

Swift (File Upload)

import Foundation

let url = URL(string: "https://api.iapp.co.th/ocr/v3/receipt/file")!
let filePath = "/path/to/receipt.jpg"
let apiKey = "YOUR_API_KEY"

var request = URLRequest(url: url)
request.httpMethod = "POST"
request.setValue(apiKey, forHTTPHeaderField: "apikey")

let boundary = UUID().uuidString
request.setValue("multipart/form-data; boundary=\(boundary)", forHTTPHeaderField: "Content-Type")

var body = Data()
body.append("--\(boundary)\r\n".data(using: .utf8)!)
body.append("Content-Disposition: form-data; name=\"file\"; filename=\"receipt.jpg\"\r\n".data(using: .utf8)!)
body.append("Content-Type: image/jpeg\r\n\r\n".data(using: .utf8)!)
body.append(try! Data(contentsOf: URL(fileURLWithPath: filePath)))
body.append("\r\n--\(boundary)\r\n".data(using: .utf8)!)
body.append("Content-Disposition: form-data; name=\"return_image\"\r\n\r\nfalse\r\n".data(using: .utf8)!)
body.append("--\(boundary)\r\n".data(using: .utf8)!)
body.append("Content-Disposition: form-data; name=\"return_ocr\"\r\n\r\nfalse\r\n".data(using: .utf8)!)
body.append("--\(boundary)--\r\n".data(using: .utf8)!)

request.httpBody = body

let task = URLSession.shared.dataTask(with: request) { data, response, error in
    guard let data = data, error == nil else {
        print("Error: \(error?.localizedDescription ?? "Unknown error")")
        return
    }
    print(String(data: data, encoding: .utf8)!)
}

task.resume()

Swift (Base64)

import Foundation

let url = URL(string: "https://api.iapp.co.th/ocr/v3/receipt/base64")!
let filePath = "/path/to/receipt.jpg"
let apiKey = "YOUR_API_KEY"

// Read image file and convert to base64
guard let imageData = try? Data(contentsOf: URL(fileURLWithPath: filePath)) else {
    print("Error reading file")
    return
}
let base64String = imageData.base64EncodedString()

let parameters: [String: Any] = [
    "base64_string": base64String,
    "return_image": false,
    "return_ocr": false
]

var request = URLRequest(url: url)
request.httpMethod = "POST"
request.setValue("application/json", forHTTPHeaderField: "Content-Type")
request.setValue(apiKey, forHTTPHeaderField: "apikey")
request.httpBody = try? JSONSerialization.data(withJSONObject: parameters)

let task = URLSession.shared.dataTask(with: request) { data, response, error in
    guard let data = data, error == nil else {
        print("Error: \(error?.localizedDescription ?? "Unknown error")")
        return
    }
    print(String(data: data, encoding: .utf8)!)
}

task.resume()

Kotlin (File Upload)

import okhttp3.*
import java.io.File

val client = OkHttpClient()
val apiKey = "YOUR_API_KEY"
val filePath = "/path/to/receipt.jpg"
val url = "https://api.iapp.co.th/ocr/v3/receipt/file"

val file = File(filePath)
val requestBody = MultipartBody.Builder()
    .setType(MultipartBody.FORM)
    .addFormDataPart("file", file.name, RequestBody.create(MediaType.parse("image/jpeg"), file))
    .addFormDataPart("return_image", "false")
    .addFormDataPart("return_ocr", "false")
    .build()

val request = Request.Builder()
    .url(url)
    .post(requestBody)
    .addHeader("apikey", apiKey)
    .build()

client.newCall(request).enqueue(object : Callback {
    override fun onFailure(call: Call, e: IOException) {
        e.printStackTrace()
    }

    override fun onResponse(call: Call, response: Response) {
        response.use {
            if (!response.isSuccessful) throw IOException("Unexpected code $response")
            println(response.body()?.string())
        }
    }
})

Kotlin (Base64)

import okhttp3.*
import java.io.File
import android.util.Base64
import org.json.JSONObject

fun processBase64Image() {
    val client = OkHttpClient()
    val apiKey = "YOUR_API_KEY"
    val filePath = "/path/to/receipt.jpg"
    val url = "https://api.iapp.co.th/ocr/v3/receipt/base64"

    // Read file and convert to base64
    val file = File(filePath)
    val bytes = file.readBytes()
    val base64String = Base64.encodeToString(bytes, Base64.DEFAULT)

    val json = JSONObject()
    json.put("base64_string", base64String)
    json.put("return_image", false)
    json.put("return_ocr", false)

    val requestBody = RequestBody.create(
        MediaType.parse("application/json"),
        json.toString()
    )

    val request = Request.Builder()
        .url(url)
        .post(requestBody)
        .addHeader("Content-Type", "application/json")
        .addHeader("apikey", apiKey)
        .build()

    client.newCall(request).enqueue(object : Callback {
        override fun onFailure(call: Call, e: IOException) {
            e.printStackTrace()
        }

        override fun onResponse(call: Call, response: Response) {
            response.use {
                if (!response.isSuccessful) throw IOException("Unexpected code $response")
                println(response.body()?.string())
            }
        }
    })
}

Java (File Upload)

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

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

        String apiKey = "YOUR_API_KEY";
        String url = "https://api.iapp.co.th/ocr/v3/receipt/file";
        String filePath = "/path/to/receipt.jpg";

        File file = new File(filePath);
        RequestBody requestBody = new MultipartBody.Builder()
            .setType(MultipartBody.FORM)
            .addFormDataPart("file", file.getName(), RequestBody.create(MediaType.parse("image/jpeg"), file))
            .addFormDataPart("return_image", "false")
            .addFormDataPart("return_ocr", "false")
            .build();

        Request request = new Request.Builder()
            .url(url)
            .post(requestBody)
            .addHeader("apikey", apiKey)
            .build();

        client.newCall(request).enqueue(new Callback() {
            @Override
            public void onFailure(Call call, IOException e) {
                e.printStackTrace();
            }

            @Override
            public void onResponse(Call call, Response response) throws IOException {
                if (!response.isSuccessful()) throw new IOException("Unexpected code " + response);
                System.out.println(response.body().string());
            }
        });
    }
}

Java (Base64)

import okhttp3.*;
import java.io.File;
import java.io.IOException;
import java.util.Base64;
import java.nio.file.Files;
import org.json.JSONObject;

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

        String apiKey = "YOUR_API_KEY";
        String url = "https://api.iapp.co.th/ocr/v3/receipt/base64";
        String filePath = "/path/to/receipt.jpg";

        try {
            // Read file and convert to base64
            byte[] fileContent = Files.readAllBytes(new File(filePath).toPath());
            String base64String = Base64.getEncoder().encodeToString(fileContent);

            JSONObject json = new JSONObject();
            json.put("base64_string", base64String);
            json.put("return_image", false);
            json.put("return_ocr", false);

            RequestBody requestBody = RequestBody.create(
                MediaType.parse("application/json"),
                json.toString()
            );

            Request request = new Request.Builder()
                .url(url)
                .post(requestBody)
                .addHeader("Content-Type", "application/json")
                .addHeader("apikey", apiKey)
                .build();

            client.newCall(request).enqueue(new Callback() {
                @Override
                public void onFailure(Call call, IOException e) {
                    e.printStackTrace();
                }

                @Override
                public void onResponse(Call call, Response response) throws IOException {
                    if (!response.isSuccessful()) throw new IOException("Unexpected code " + response);
                    System.out.println(response.body().string());
                }
            });
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

Dart (File Upload)

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

String url = 'https://api.iapp.co.th/ocr/v3/receipt/file';
String filePath = '/path/to/receipt.jpg';
String apiKey = 'YOUR_API_KEY';

void main() async {
    var url = Uri.parse(url);
    var request = http.MultipartRequest('POST', url)
        ..headers['apikey'] = apiKey
        ..files.add(await http.MultipartFile.fromPath('file', filePath))
        ..fields['return_image'] = 'false'
        ..fields['return_ocr'] = 'false';

    var response = await request.send();

    if (response.statusCode == 200) {
        var responseData = await response.stream.bytesToString();
        print(responseData);
    } else {
        print('Error: ${response.statusCode}');
    }
}

Dart (Base64)

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

void main() async {
    String url = 'https://api.iapp.co.th/ocr/v3/receipt/base64';
    String filePath = '/path/to/receipt.jpg';
    String apiKey = 'YOUR_API_KEY';

    try {
        // Read file and convert to base64
        File file = File(filePath);
        List<int> fileBytes = await file.readAsBytes();
        String base64String = base64Encode(fileBytes);

        Map<String, dynamic> data = {
            'base64_string': base64String,
            'return_image': false,
            'return_ocr': false
        };

        var response = await http.post(
            Uri.parse(url),
            headers: {
                'Content-Type': 'application/json',
                'apikey': apiKey
            },
            body: jsonEncode(data)
        );

        if (response.statusCode == 200) {
            print(response.body);
        } else {
            print('Error: ${response.statusCode}');
        }
    } catch (e) {
        print('Error: $e');
    }
}

Limitations & Best Practices

Limitations

• Maximum file size: 10MB
• Supported languages: Thai
• PDF files: Up to 10 pages
• Rate limit: 10 requests per second per API key

Best Practices

1. Ensure good image quality for optimal results
2. Use JPEG or PNG format for images
3. Implement error handling for failed requests
4. Cache responses when processing the same document multiple times
5. Set appropriate timeouts for large files

Accuracy & Performance

Overall Accuracy

Based on our benchmark dataset of 10,000 Thai receipts:

Field Type	Accuracy (%)	Notes
Invoice Numbers	99.2%	Including tax invoice numbers
Amounts	99.5%	Currency values and totals
Dates	98.7%	Various Thai date formats
Line Items	97.8%	Product details and prices
Overall	98.8%	Weighted average

Processing Speed

• Average processing time: 5-10 seconds
• 95th percentile: 12 seconds
• Maximum processing time: 15 seconds

Factors Affecting Accuracy

1. Image Quality

   • Resolution (minimum 300 DPI recommended)
   • Lighting conditions
   • Image focus and clarity

2. Document Condition

   • Physical damage
   • Fading or wear
   • Handwritten modifications

3. Receipt Format

   • Standard formats: 99%+ accuracy
   • Non-standard layouts: 95%+ accuracy
   • Handwritten elements: 90%+ accuracy

History

Our model is continuously trained on new data to improve accuracy:

Version	Release Date	Accuracy	Key Improvements
3.0	2024-12-27	96.5%	Base version

Pricing

AI API Service Name	Endpoint	Pricing	On-Premise
Receipt OCR [v1.0]	receipt-ocr	1 IC/Page	Contact