Create a charge with a custom tiered application fee

create_charge_with_tiered_app_fee.php

<?php 
// Include Stripe's library and set your API key. 
require('./config.php');

// Retrieve the account ID and application fee tier details from your own database...
// In this example $db is an object containing the attributes you retrieve from your database.

// Calculate the app fee to charge based on the pricing tier
if ($db->pricing_tier == 1){
  // Charge 2.9% + $.30 per charge (passing Stripe's default processing fees)
  $application_fee = ($db->amount/100 * .029 + .30) * 100;  
}
elseif ($db->pricing_tier == 2){
  // Charge 4% + $.50 per charge
  $application_fee = ($db->amount/100 * .04 + .50) * 100;  
}
elseif ($db->pricing_tier == 3){
  // Charge 5% only per charge
  $application_fee = ($db->amount/100 * .05) * 100;  
}

// Check for a submitted token
if (isset($_POST['stripeToken'])){
  try {
    $charge = \Stripe\Charge::create(array(
      "amount" => $db->amount, // The total amount to charge the customer, in cents
      "currency" => "usd",
      "source" => $token, // The token submitted from Checkout or Stripe.js
      "application_fee" => $application_fee,
      "destination" => $db->connected_account_id, // The account ID, retrieved from your database
    ));
    $success = "Thanks! Your payment has been made";
  }
  catch(\Stripe\Error\Card $e) {
    // Since it's a decline, \Stripe\Error\Card will be caught
    $body = $e->getJsonBody();
    $error  = $body['error']['message']; // Display the $error message to the user in your app
  } catch (\Stripe\Error\RateLimit $e) {
    // Rate limits are pretty rare. Maybe have the user try again?
  } catch (\Stripe\Error\InvalidRequest $e) {
    // You made an invalid request to Stripe. Maybe log or send yourself an email?
  } catch (\Stripe\Error\Authentication $e) {
    // You used a bad API key
  } catch (\Stripe\Error\ApiConnection $e) {
    // There was a connectivity problem. Maybe log and have the user try again?
  } catch (\Stripe\Error\Base $e) {
    // Some other API error. Maybe log or send yourself an email?
  } catch (Exception $e) {
    // Something unrelated to Stripe happened. Log or send yourself an email, etc
  }
}