Integrate Licfy Into Your Own Plugin or Theme

Licfy is a license management platform: you sign up, register your own plugin or theme as a product, and sell license keys to your customers. This guide shows you exactly how to add license protection to your product's code using the Licfy REST API — no need to build your own licensing system from scratch.

1. Register Your Product

After creating your account, Go to Licfy → Products and add your plugin or theme. Give it a unique product slug (for example my-awesome-plugin) — you will use this exact slug in your verification requests, so make sure it matches the one you hard-code into your product.

2. Get Your API Token

After registering your product, go to Licfy → API Token in your WordPress admin and generate a token. This token identifies you (the seller) when your product calls the verification API — it is not the same as a customer's license key, and it should never be shown to your customers.

3. Issue Licenses to Customers

Create a Package under Licfy → Packages to define how many domains a license can be activated on and how many days it stays valid. Then, every time someone buys your product, create a License under Licfy → Licenses for that client — Licfy generates a unique license key you deliver to your customer (for example inside their purchase receipt email).

4. Add a License Field to Your Product

Inside your own plugin or theme, add a simple settings field where your customer pastes the license key you sent them:

<form method="post">
    <input type="text" name="my_plugin_license_key" placeholder="Enter your license key" />
    <button type="submit">Activate License</button>
</form>

When this form is submitted, your plugin sends the key to Licfy for verification (next step).

5. Verify Licenses From Your Code

Call the /verify endpoint from your product's PHP code using wp_remote_post(). Send your API token (from step 1) as a Bearer header, and the customer's license key plus your product slug in the body:

function my_plugin_verify_license( $license_key ) {
    $response = wp_remote_post( 'https://licfy.com/api/licfy/v1/verify', array(
        'timeout' => 15,
        'headers' => array(
            'Authorization' => 'Bearer YOUR_LICFY_API_TOKEN', // from Licfy → API Token
            'Content-Type'  => 'application/json',
        ),
        'body' => wp_json_encode( array(
            'email'        => get_option( 'admin_email' ),
            'license_key'  => $license_key,
            'product_slug' => 'my-awesome-plugin',   // must match your Licfy product slug
            'website_name' => get_bloginfo( 'name' ),
            'website_url'  => home_url(),
        ) ),
    ) );

    if ( is_wp_error( $response ) ) {
        return array( 'status' => 'error', 'message' => $response->get_error_message() );
    }

    return json_decode( wp_remote_retrieve_body( $response ), true );
}

A successful response looks like this:

{
    "status": "200",
    "license_status": "valid",
    "message": "License verified",
    "package_name": "Pro Yearly",
    "license_key": "506067C1-F855664F-3C9121CA-4B9D7026",
    "domains": ["https://example.com"],
    "expired_date": "2027-01-01 00:00:00",
    "left_days": 365
}

6. Cache the Result & Gate Your Features

Don't call the API on every page load. Cache the result with a transient and re-check periodically (for example once a day):

function my_plugin_is_licensed() {
    $cached = get_transient( 'my_plugin_license_status' );
    if ( false !== $cached ) {
        return 'valid' === $cached;
    }

    $license_key = get_option( 'my_plugin_license_key' );
    if ( ! $license_key ) {
        return false;
    }

    $result = my_plugin_verify_license( $license_key );
    $status = ( ! empty( $result['license_status'] ) && 'valid' === $result['license_status'] ) ? 'valid' : 'invalid';

    set_transient( 'my_plugin_license_status', $status, DAY_IN_SECONDS );

    return 'valid' === $status;
}

// Anywhere in your plugin:
if ( my_plugin_is_licensed() ) {
    // unlock premium features / updates
}

Full Integration Example

A complete, drop-in class you can adapt for your own plugin:

class My_Plugin_Licfy_Client {

    const API_URL      = 'https://licfy.com/api/licfy/v1/verify';
    const API_TOKEN     = 'YOUR_LICFY_API_TOKEN';
    const PRODUCT_SLUG  = 'my-awesome-plugin';

    public static function verify( $license_key ) {
        $response = wp_remote_post( self::API_URL, array(
            'timeout' => 15,
            'headers' => array(
                'Authorization' => 'Bearer ' . self::API_TOKEN,
                'Content-Type'  => 'application/json',
            ),
            'body' => wp_json_encode( array(
                'email'        => get_option( 'admin_email' ),
                'license_key'  => $license_key,
                'product_slug' => self::PRODUCT_SLUG,
                'website_name' => get_bloginfo( 'name' ),
                'website_url'  => home_url(),
            ) ),
        ) );

        if ( is_wp_error( $response ) ) {
            return array( 'status' => 'error', 'message' => $response->get_error_message() );
        }

        return json_decode( wp_remote_retrieve_body( $response ), true );
    }

    public static function is_active() {
        $cached = get_transient( 'my_plugin_license_status' );
        if ( false !== $cached ) {
            return 'valid' === $cached;
        }

        $license_key = get_option( 'my_plugin_license_key' );
        if ( ! $license_key ) {
            return false;
        }

        $result = self::verify( $license_key );
        $status = ( ! empty( $result['license_status'] ) && 'valid' === $result['license_status'] ) ? 'valid' : 'invalid';
        set_transient( 'my_plugin_license_status', $status, DAY_IN_SECONDS );

        return 'valid' === $status;
    }
}

REST API Reference

All endpoints are namespaced under https://licfy.com/api/licfy/v1.

Verify & Activate a License

Request Body

Common Responses

Frequently Asked Questions