diff --git a/packaging/tags.py b/packaging/tags.py
index a0e1ea23..4314cb33 100644
--- a/packaging/tags.py
+++ b/packaging/tags.py
@@ -4,6 +4,7 @@
 
 import logging
 import platform
+import struct
 import subprocess
 import sys
 import sysconfig
@@ -37,7 +38,7 @@
 }
 
 
-_32_BIT_INTERPRETER = sys.maxsize <= 2**32
+_32_BIT_INTERPRETER = (struct.calcsize("P") == 4)
 
 
 class Tag: