diff --git a/requirements.txt b/requirements.txt
index f14b614..fdf6caa 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,2 +1,3 @@
 requests==2.31.0
 beautifulsoup4==4.12.2
+idna==3.6
diff --git a/save_iana_domains.py b/save_iana_domains.py
index cff6fb7..b9c19e5 100644
--- a/save_iana_domains.py
+++ b/save_iana_domains.py
@@ -11,6 +11,7 @@ import time
 import json
 import os
 from datetime import datetime
+import idna
 
 def fetch_domain_details(extension, url):
     """Fetch detailed information for a specific domain extension"""
@@ -183,7 +184,13 @@ def fetch_iana_domains():
                 domain_text = domain_text[1:]
             
             if domain_text and len(domain_text) > 0:
-                url = urljoin(base_url, f"/domains/root/db/{domain_text}.html")
+                # Convert to Punycode for URL if it contains non-ASCII characters
+                try:
+                    punycode_extension = idna.encode(domain_text).decode('ascii')
+                    url = urljoin(base_url, f"/domains/root/db/{punycode_extension}.html")
+                except (idna.IDNAError, UnicodeError):
+                    # Fallback to original if Punycode conversion fails
+                    url = urljoin(base_url, f"/domains/root/db/{domain_text}.html")
                 
                 domains.append({
                     'extension': domain_text,