diff --git a/discordsend_utils/discord_api.py b/discordsend_utils/discord_api.py
index 8adfa83..0b2e75e 100644
--- a/discordsend_utils/discord_api.py
+++ b/discordsend_utils/discord_api.py
@@ -20,8 +20,8 @@ logger = logging.getLogger("comfyui_discordsend")
 
 # Discord webhook URL patterns
 WEBHOOK_URL_PATTERNS = [
-    r"https?://(?:www\.)?discord(?:app)?\.com/api/webhooks/\d+/[\w-]+$",
-    r"https?://(?:www\.)?discordapp\.com/api/webhooks/\d+/[\w-]+$",
+    r"https://(?:www\.)?discord(?:app)?\.com/api/webhooks/\d+/[\w-]+$",
+    r"https://(?:www\.)?discordapp\.com/api/webhooks/\d+/[\w-]+$",
 ]
 
 
@@ -38,8 +38,8 @@ def validate_webhook_url(url: str) -> Tuple[bool, str]:
     if not url:
         return False, "Webhook URL is empty"
     
-    if not url.startswith("http"):
-        return False, "Webhook URL must start with http:// or https://"
+    if not url.startswith("https://"):
+        return False, "Webhook URL must start with https://"
     
     # Check against known patterns
     for pattern in WEBHOOK_URL_PATTERNS:
diff --git a/tests/test_utils.py b/tests/test_utils.py
index 7fc5c57..e455c9a 100644
--- a/tests/test_utils.py
+++ b/tests/test_utils.py
@@ -131,6 +131,12 @@ class TestWebhookValidation(unittest.TestCase):
         is_valid, message = validate_webhook_url("http://localhost:8080/admin")
         self.assertFalse(is_valid)
 
+    def test_http_url_rejected(self):
+        """Should reject HTTP URLs (must be HTTPS)."""
+        is_valid, message = validate_webhook_url("http://discord.com/api/webhooks/123/abc")
+        self.assertFalse(is_valid)
+        self.assertIn("must start with https://", message)
+
     def test_ip_encoding_urls(self):
         """Should reject alternate IP encodings."""
         self.assertFalse(validate_webhook_url("http://127.0.0.1")[0])