PHP Examples

Ready-to-use PHP code to integrate CaptchaKings API into your application.

📦 Requirements: PHP 7.0+ with cURL extension (usually enabled by default)

Quick Start (Recommended)

The easiest way to integrate is using our official PHP library. Download CaptchaKings.php

php

<?php

require_once 'CaptchaKings.php';

try {
    // Initialize with your API Key
    $ck = new CaptchaKings('ck_your_api_key_here');
    
    // Solve CAPTCHA
    $result = $ck->solve('/path/to/captcha.jpg');
    
    if ($result['success']) {
        echo "Prediction: " . $result['data']['prediction'];
    } else {
        echo "Error: " . $result['error'];
    }
    
} catch (Exception $e) {
    echo "Error: " . $e->getMessage();
}

?>

Raw PHP Example

Here's the simplest way to solve a CAPTCHA with PHP:

php

<?php

$apiKey = 'ck_your_api_key_here';
$imagePath = '/path/to/captcha.jpg';

// Initialize cURL
$ch = curl_init('https://captchakings.com/api/process.php');

// Set options
curl_setopt_array($ch, [
    CURLOPT_POST => true,
    CURLOPT_POSTFIELDS => [
        'captcha' => new CURLFile($imagePath)
    ],
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_HTTPHEADER => [
        'Authorization: Bearer ' . $apiKey
    ]
]);

// Execute
$response = curl_exec($ch);
$httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
curl_close($ch);

// Parse response
$result = json_decode($response, true);

if ($httpCode === 200 && $result['success']) {
    echo "✅ CAPTCHA Solved: " . $result['data']['prediction'] . "\n";
    echo "Confidence: " . $result['data']['confidence'] . "\n";
    echo "Credits Remaining: " . $result['credits']['credits_remaining'] . "\n";
} else {
    echo "❌ Error: " . ($result['error'] ?? 'Unknown error') . "\n";
}

?>

Complete Example with Error Handling

Production-ready code with comprehensive error handling:

php

<?php

function solveCaptcha($apiKey, $imagePath) {
    $url = 'https://captchakings.com/api/process.php';
    
    // Validate file exists
    if (!file_exists($imagePath)) {
        return [
            'success' => false,
            'error' => 'File not found: ' . $imagePath
        ];
    }
    
    // Prepare cURL request
    $ch = curl_init($url);
    curl_setopt_array($ch, [
        CURLOPT_POST => true,
        CURLOPT_POSTFIELDS => [
            'captcha' => new CURLFile(
                $imagePath,
                mime_content_type($imagePath),
                'captcha.jpg'
            )
        ],
        CURLOPT_RETURNTRANSFER => true,
        CURLOPT_HTTPHEADER => [
            'Authorization: Bearer ' . $apiKey
        ],
        CURLOPT_TIMEOUT => 30,
        CURLOPT_SSL_VERIFYPEER => true
    ]);
    
    // Execute request
    $response = curl_exec($ch);
    $httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    $curlError = curl_error($ch);
    curl_close($ch);
    
    // Handle cURL errors
    if ($curlError) {
        return [
            'success' => false,
            'error' => 'Connection error: ' . $curlError
        ];
    }
    
    // Parse JSON response
    $data = json_decode($response, true);
    if (json_last_error() !== JSON_ERROR_NONE) {
        return [
            'success' => false,
            'error' => 'Invalid JSON response: ' . json_last_error_msg()
        ];
    }
    
    // Handle HTTP errors
    if ($httpCode !== 200) {
        return [
            'success' => false,
            'error' => $data['error'] ?? 'Unknown error (HTTP ' . $httpCode . ')'
        ];
    }
    
    return $data;
}

// Usage Example
$apiKey = 'ck_your_api_key_here';
$imagePath = '/path/to/captcha.jpg';

$result = solveCaptcha($apiKey, $imagePath);

if ($result['success']) {
    echo "✅ CAPTCHA Solved!\n";
    echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━\n";
    echo "Prediction:        " . $result['data']['prediction'] . "\n";
    echo "Confidence:        " . $result['data']['confidence'] . "\n";
    echo "Process Time:      " . $result['data']['process_time'] . "s\n";
    echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━\n";
    echo "Credits Deducted:  " . $result['credits']['credits_deducted'] . "\n";
    echo "Credits Remaining: " . $result['credits']['credits_remaining'] . "\n";
    echo "Plan:              " . $result['credits']['plan'] . "\n";
} else {
    echo "❌ Error: " . $result['error'] . "\n";
    
    // Handle specific errors
    if (strpos($result['error'], 'Invalid API key') !== false) {
        echo "\n💡 Tip: Check your API key in the dashboard\n";
        echo "   URL: https://captchakings.com/dashboard\n";
    } elseif (strpos($result['error'], 'Insufficient credits') !== false) {
        echo "\n💡 Tip: Please top up your credits\n";
        echo "   URL: https://captchakings.com/dashboard#credits\n";
    }
}

?>

Class-Based Implementation

Object-oriented approach for better code organization:

php

<?php

class CaptchaKingsAPI {
    private $apiKey;
    private $baseUrl = 'https://captchakings.com/api/process.php';
    
    public function __construct($apiKey) {
        $this->apiKey = $apiKey;
    }
    
    public function solve($imagePath) {
        if (!file_exists($imagePath)) {
            throw new Exception('Image file not found: ' . $imagePath);
        }
        
        $ch = curl_init($this->baseUrl);
        curl_setopt_array($ch, [
            CURLOPT_POST => true,
            CURLOPT_POSTFIELDS => [
                'captcha' => new CURLFile($imagePath)
            ],
            CURLOPT_RETURNTRANSFER => true,
            CURLOPT_HTTPHEADER => [
                'Authorization: Bearer ' . $this->apiKey
            ],
            CURLOPT_TIMEOUT => 30
        ]);
        
        $response = curl_exec($ch);
        $httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
        $error = curl_error($ch);
        curl_close($ch);
        
        if ($error) {
            throw new Exception('cURL error: ' . $error);
        }
        
        $data = json_decode($response, true);
        
        if ($httpCode !== 200 || !$data['success']) {
            throw new Exception($data['error'] ?? 'API request failed');
        }
        
        return $data;
    }
    
    public function getCredits() {
        // You can implement this to check remaining credits
        // without solving a CAPTCHA
    }
}

// Usage
try {
    $api = new CaptchaKingsAPI('ck_your_api_key_here');
    $result = $api->solve('/path/to/captcha.jpg');
    
    echo "Solved: " . $result['data']['prediction'] . "\n";
    echo "Credits: " . $result['credits']['credits_remaining'] . "\n";
    
} catch (Exception $e) {
    echo "Error: " . $e->getMessage() . "\n";
}

?>

Laravel Integration

If you're using Laravel, here's how to integrate:

1. Create Service Class

php

<?php
// app/Services/CaptchaKingsService.php

namespace App\Services;

use Illuminate\Support\Facades\Http;

class CaptchaKingsService
{
    protected $apiKey;
    protected $baseUrl = 'https://captchakings.com/api/process.php';
    
    public function __construct()
    {
        $this->apiKey = config('services.captchakings.api_key');
    }
    
    public function solve($imagePath)
    {
        $response = Http::withHeaders([
            'Authorization' => 'Bearer ' . $this->apiKey
        ])->attach(
            'captcha',
            file_get_contents($imagePath),
            'captcha.jpg'
        )->post($this->baseUrl);
        
        if (!$response->successful()) {
            throw new \Exception('API request failed: ' . $response->json('error'));
        }
        
        return $response->json();
    }
}
?>

2. Add to config/services.php

php

return [
    // ...
    
    'captchakings' => [
        'api_key' => env('CAPTCHAKINGS_API_KEY'),
    ],
];

3. Add to .env

bash

CAPTCHAKINGS_API_KEY=ck_your_api_key_here

4. Use in Controller

php

<?php

namespace App\Http\Controllers;

use App\Services\CaptchaKingsService;
use Illuminate\Http\Request;

class CaptchaController extends Controller
{
    protected $captchaService;
    
    public function __construct(CaptchaKingsService $captchaService)
    {
        $this->captchaService = $captchaService;
    }
    
    public function solve(Request $request)
    {
        $request->validate([
            'captcha_image' => 'required|image|max:5120'
        ]);
        
        try {
            $result = $this->captchaService->solve(
                $request->file('captcha_image')->path()
            );
            
            return response()->json([
                'success' => true,
                'prediction' => $result['data']['prediction'],
                'confidence' => $result['data']['confidence'],
                'credits_remaining' => $result['credits']['credits_remaining']
            ]);
            
        } catch (\Exception $e) {
            return response()->json([
                'success' => false,
                'error' => $e->getMessage()
            ], 400);
        }
    }
}
?>

WordPress Integration

For WordPress plugins or themes:

php

<?php

function solve_captcha_with_captchakings($image_path) {
    $api_key = get_option('captchakings_api_key');
    $url = 'https://captchakings.com/api/process.php';
    
    $response = wp_remote_post($url, [
        'headers' => [
            'Authorization' => 'Bearer ' . $api_key
        ],
        'body' => [
            'captcha' => new CURLFile($image_path)
        ],
        'timeout' => 30
    ]);
    
    if (is_wp_error($response)) {
        return [
            'success' => false,
            'error' => $response->get_error_message()
        ];
    }
    
    $data = json_decode(wp_remote_retrieve_body($response), true);
    
    return $data;
}

// Usage
$result = solve_captcha_with_captchakings('/path/to/captcha.jpg');

if ($result['success']) {
    echo 'CAPTCHA solved: ' . $result['data']['prediction'];
} else {
    echo 'Error: ' . $result['error'];
}

?>

Common Use Cases

Batch Processing

Process multiple CAPTCHAs in sequence:

php

<?php

$apiKey = 'ck_your_api_key_here';
$images = glob('/path/to/captchas/*.jpg');

$results = [];

foreach ($images as $image) {
    echo "Processing: " . basename($image) . "...\n";
    
    $result = solveCaptcha($apiKey, $image);
    
    if ($result['success']) {
        $results[] = [
            'file' => basename($image),
            'prediction' => $result['data']['prediction'],
            'confidence' => $result['data']['confidence']
        ];
        echo "✓ Solved: " . $result['data']['prediction'] . "\n";
    } else {
        echo "✗ Error: " . $result['error'] . "\n";
    }
    
    // Be nice to the API - small delay between requests
    usleep(500000); // 0.5 second
}

echo "\n" . count($results) . " CAPTCHAs solved successfully!\n";

?>

With Retry Logic

Automatically retry failed requests:

php

<?php

function solveCaptchaWithRetry($apiKey, $imagePath, $maxRetries = 3) {
    $attempts = 0;
    
    while ($attempts < $maxRetries) {
        $attempts++;
        $result = solveCaptcha($apiKey, $imagePath);
        
        if ($result['success']) {
            return $result;
        }
        
        // Don't retry if it's an authentication or credit error
        if (strpos($result['error'], 'Invalid API key') !== false ||
            strpos($result['error'], 'Insufficient credits') !== false) {
            return $result;
        }
        
        echo "Attempt $attempts failed, retrying...\n";
        sleep(2); // Wait 2 seconds before retry
    }
    
    return $result;
}

$result = solveCaptchaWithRetry('ck_your_api_key_here', '/path/to/captcha.jpg');

?>

Tips & Best Practices

Store API keys securely - Use environment variables, never hardcode
Handle errors gracefully - Always check for success in response
Implement timeout - Set CURLOPT_TIMEOUT to avoid hanging
Verify SSL - Always use CURLOPT_SSL_VERIFYPEER => true
Check credits - Monitor credits_remaining to avoid running out
Respect rate limits - Don't send too many requests at once