diff --git a/lib/bitcoin.py b/lib/bitcoin.py
index 0dcc3dff..28d07e60 100644
--- a/lib/bitcoin.py
+++ b/lib/bitcoin.py
@@ -163,11 +163,11 @@ def is_old_seed(seed):
 
     try:
         seed.decode('hex')
-        is_hex = (len(seed) == 32)
+        is_hex = (len(seed) == 32 or len(seed) == 64)
     except Exception:
         is_hex = False
 
-    return is_hex or (uses_electrum_words and len(words) == 12)
+    return is_hex or (uses_electrum_words and (len(words) == 12 or len(words) == 24))
 
 
 # pywallet openssl private key implementation