A simple snippet to check the TLS version and ciphers for Realex (https://www.realexpayments.com/support/tls-faq/)

check-tls-version.php

<?php 

$recommendedCiphers = [
    'TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384',
    'TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384',
];

$supportedCiphers = [
    'TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256',
    'TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256',
    'TLS_RSA_WITH_AES_256_GCM_SHA384',
    'TLS_RSA_WITH_AES_128_GCM_SHA256',
];

$ch = curl_init('https://www.howsmyssl.com/a/check');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$responseData = curl_exec($ch);
curl_close($ch);
$response = json_decode($responseData);

echo 'TLS version: ' . $response->tls_version . PHP_EOL . PHP_EOL;
echo 'Recommended Ciphers status:' . PHP_EOL;

foreach ($recommendedCiphers as $recommendedCipher) {
    if (in_array($recommendedCipher, $response->given_cipher_suites)) {
        echo ' -> ' . $recommendedCipher . ' - supported' . PHP_EOL;
        continue;
    }

    echo ' -> ' . $recommendedCipher . ' - not supported' . PHP_EOL;
}

echo PHP_EOL;
echo 'Supported Ciphers status:' . PHP_EOL;

foreach ($supportedCiphers as $supportedCipher) {
    if (in_array($supportedCipher, $response->given_cipher_suites)) {
        echo ' -> ' . $supportedCipher . ' - supported' . PHP_EOL;
        continue;
    }

    echo ' -> ' . $supportedCipher . ' - not supported' . PHP_EOL;
}