Verify emails in PHP with Verifly

Email verification in PHP applications

PHP still powers a huge share of the web — Laravel and Symfony apps, WordPress and its plugin ecosystem, and countless bespoke scripts behind contact forms. Every one of them collects email addresses, and every one of them faces the same trap: PHP's filter_var with FILTER_VALIDATE_EMAIL only confirms the string is well-formed. It cannot tell you the mailbox exists, that the domain is a disposable throwaway, or that the address is a generic role inbox that will never engage.

Verifly answers that with a single HTTP request. You have two natural clients in PHP: the ext-curl functions that ship with virtually every install, or the Guzzle library that Laravel and Symfony already pull in. Either way you send an address with a Bearer header, Verifly runs a live SMTP mailbox probe, and json_decode gives you an associative array with a result of deliverable, undeliverable, or risky plus flags for disposable, role, catch-all, and smtp. That drops straight into an if or match expression.

Because Verifly is pay-as-you-go — $2 per 1,000 checks down to $0.60 per 1,000 at volume — it works for a low-traffic WordPress contact form and a high-volume SaaS signup alike, with no monthly plan to commit to. Self-register for 100 free credits with no card and no captcha, store the vf_ key in your .env, and reuse it everywhere.

Batch-verify emails with Guzzle

For a list of addresses, send them together to /verify/batch instead of firing one request per row. Post a JSON body with an emails array and read back a results array in order. Guzzle makes this concise, and json_decode turns the response into arrays you can filter with array_filter.

use GuzzleHttp\Client;

$client = new Client();
$emails = ['ada@example.com', 'info@some-domain.com', 'noreply@disposable.tld'];

$response = $client->post('https://verifly.email/api/v1/verify/batch', [
    'headers' => ['Authorization' => 'Bearer vf_YOUR_KEY'],
    'json'    => ['emails' => $emails],
]);

$results = json_decode((string) $response->getBody(), true)['results'];
$clean = array_filter($results, fn($r) => $r['result'] === 'deliverable');

printf("Keeping %d of %d\n", count($clean), count($results));
foreach ($results as $r) {
    if (!empty($r['disposable']) || !empty($r['role'])) {
        echo 'drop: ' . $r['email'] . ' (' . $r['result'] . ')' . PHP_EOL;
    }
}

Validate at signup in Laravel

The highest-leverage place to verify in a PHP app is the registration request. A custom validation rule or a quick check in your controller — with a short cURL timeout so a slow probe never hangs the request, and fail-open behaviour on error so signups are never blocked by an outage — lets you reject disposable addresses and warn on undeliverable ones before the user row is written.

function emailOk(string $email): bool {
    $ch = curl_init(
        'https://verifly.email/api/v1/verify?email=' . urlencode($email)
    );
    curl_setopt_array($ch, [
        CURLOPT_RETURNTRANSFER => true,
        CURLOPT_TIMEOUT        => 8,
        CURLOPT_HTTPHEADER     => ['Authorization: Bearer vf_YOUR_KEY'],
    ]);
    $body = curl_exec($ch);
    curl_close($ch);

    if ($body === false) {
        return true; // fail open on network error
    }
    $data = json_decode($body, true);
    if (!empty($data['disposable'])) {
        return false;
    }
    return ($data['result'] ?? '') !== 'undeliverable';
}