diff --git a/src/Casters/NotificationAmountCaster.php b/src/Casters/NotificationAmountCaster.php
new file mode 100644
index 0000000..d3b5abe
--- /dev/null
+++ b/src/Casters/NotificationAmountCaster.php
@@ -0,0 +1,13 @@
+<?php
+
+namespace Creagia\Redsys\Casters;
+
+use Spatie\DataTransferObject\Caster;
+
+class NotificationAmountCaster implements Caster
+{
+    public function cast(mixed $value): float
+    {
+        return floatval($value / 100);
+    }
+}
diff --git a/src/RedsysRequest.php b/src/RedsysRequest.php
index 4000b19..20c67b6 100644
--- a/src/RedsysRequest.php
+++ b/src/RedsysRequest.php
@@ -33,7 +33,7 @@ public function createPaymentRequest(
         ?RequestParameters $requestParameters = null
     ): array {
         $this->parameters = $requestParameters ?? new RequestParameters();
-        $this->parameters->amount = number_format(round($amount, 2) * 100, 0, '', '');
+        $this->parameters->amount = $this->formatAmount($amount);
         $this->parameters->currency = $currency->value;
         $this->parameters->merchantCode = $this->redsysClient->merchantCode;
         $this->parameters->order = $orderNumber;
@@ -49,6 +49,11 @@ public function createPaymentRequest(
         return $this->getRequestFieldsArray();
     }
 
+    private function formatAmount(float $amount): int
+    {
+        return number_format(round($amount, 2) * 100, 0, '', '');
+    }
+
     #[ArrayShape(['Ds_SignatureVersion' => "string", 'Ds_MerchantParameters' => "string", 'Ds_Signature' => "string"])]
      public function getRequestFieldsArray(): array
      {
@@ -67,13 +72,13 @@ public function getFormHtml(): string
 
         $formFields = $this->getRequestFieldsArray();
 
-        return '
-            <form action="' . $this->redsysClient->getBaseUrl() . '/realizarPago" method="post">
-            <input type="hidden" name="Ds_SignatureVersion" value="' . $formFields['Ds_SignatureVersion'] . '"/>
-            <input type="hidden" name="Ds_MerchantParameters" value="' . $formFields['Ds_MerchantParameters'] . '"/>
-            <input type="hidden" name="Ds_Signature" value="' . $formFields['Ds_Signature'] . '"/>
+        return <<<HTML
+            <form action="{$this->redsysClient->getBaseUrl()}/realizarPago" method="post">
+            <input type="hidden" name="Ds_SignatureVersion" value="{$formFields['Ds_SignatureVersion']}"/>
+            <input type="hidden" name="Ds_MerchantParameters" value="{$formFields['Ds_MerchantParameters']}"/>
+            <input type="hidden" name="Ds_Signature" value="{$formFields['Ds_Signature']}"/>
             </form>
             <script>document.forms[0].submit();</script>
-        ';
+        HTML;
     }
 }
diff --git a/src/Support/NotificationParameters.php b/src/Support/NotificationParameters.php
index 8790683..ec67bc2 100644
--- a/src/Support/NotificationParameters.php
+++ b/src/Support/NotificationParameters.php
@@ -2,6 +2,8 @@
 
 namespace Creagia\Redsys\Support;
 
+use Creagia\Redsys\Casters\NotificationAmountCaster;
+use Spatie\DataTransferObject\Attributes\CastWith;
 use Spatie\DataTransferObject\DataTransferObject;
 
 class NotificationParameters extends DataTransferObject
@@ -13,7 +15,8 @@ class NotificationParameters extends DataTransferObject
     public string $hour;
 
     #[MapTo('DS_AMOUNT')]
-    public int $amount;
+    #[CastWith(NotificationAmountCaster::class)]
+    public float $amount;
 
     #[MapTo('DS_CURRENCY')]
     public int $currency;
@@ -85,9 +88,4 @@ public function toArray(): array
     {
         return array_filter(parent::toArray());
     }
-
-    public function getAmount(): float
-    {
-        return (float) $this->amount / 100;
-    }
 }
diff --git a/tests/ResponseTest.php b/tests/ResponseTest.php
index ad0cc91..086f597 100644
--- a/tests/ResponseTest.php
+++ b/tests/ResponseTest.php
@@ -26,7 +26,7 @@
     $redsysNotification->setParametersFromResponse($responsePost);
     $result = $redsysNotification->checkResponse();
 
-    expect($result->getAmount())->toBe($this->paymentRequestAmount);
+    expect($result->amount)->toBe($this->paymentRequestAmount);
 });
 
 it('fails if signatures differ', function () {
