diff --git a/.env b/.env
index c47e2e0..3cff513 100644
--- a/.env
+++ b/.env
@@ -15,7 +15,7 @@ DB_NAME=controlpatente
 JWT_SECRET=d95810e29f700cb99d3ed6a891ace603522875069ec655887a01629891a38ce8
 
 # Admin password (optional - if not set, a random password will be generated on first run)
-# ADMIN_PASSWORD=
+# ADMIN_PASSWORD=HnXlU0BtE5-PtQ8n
 
 # Allowed origins for CORS (comma-separated)
 ALLOWED_ORIGINS=http://localhost:5173,http://127.0.0.1:5173,https://demo.v1ru5.cl
diff --git a/alpr-service/main.py b/alpr-service/main.py
index 6728744..41a4e23 100644
--- a/alpr-service/main.py
+++ b/alpr-service/main.py
@@ -143,8 +143,16 @@ def send_plate(plate_number):
         print(f"✗ Error sending plate: {e}")
 
 def validate_plate(text):
-    """Valida formato chileno"""
-    return bool(re.match(r'^[A-Z]{4}\d{2}$', text) or re.match(r'^[A-Z]{2}\d{4}$', text))
+    """Valida formatos de patentes de Chile, Argentina y Brasil"""
+    # Chile formato nuevo: XXXX00 (4 letras, 2 números)
+    # Chile formato antiguo: XX0000 (2 letras, 4 números)
+    # Argentina Mercosur: AA000AA (2 letras, 3 números, 2 letras)
+    # Brasil Mercosur: AAA0A00 (3 letras, 1 número, 1 letra, 2 números)
+    chile_new = re.match(r'^[A-Z]{4}\d{2}$', text)
+    chile_old = re.match(r'^[A-Z]{2}\d{4}$', text)
+    argentina = re.match(r'^[A-Z]{2}\d{3}[A-Z]{2}$', text)
+    brasil = re.match(r'^[A-Z]{3}\d[A-Z]\d{2}$', text)
+    return bool(chile_new or chile_old or argentina or brasil)
 
 def ocr_worker(reader, worker_id):
     """Hilo dedicado para OCR - múltiples workers para mejor rendimiento"""