diff --git a/tests/tinyproxy.py b/tests/tinyproxy.py
--- a/tests/tinyproxy.py
+++ b/tests/tinyproxy.py
@@ -14,6 +14,7 @@
 
 __version__ = "0.2.1"
 
+import io
 import optparse
 import os
 import select
@@ -25,6 +26,23 @@
     util,
 )
 
+# Ensure Windows doesn't emit CRLF.
+if sys.version_info[0] >= 3:
+    sys.stdout = io.TextIOWrapper(
+        sys.stdout.buffer,
+        sys.stdout.encoding,
+        sys.stdout.errors,
+        newline="\n",
+        line_buffering=sys.stdout.line_buffering,
+    )
+    sys.stderr = io.TextIOWrapper(
+        sys.stderr.buffer,
+        sys.stderr.encoding,
+        sys.stderr.errors,
+        newline="\n",
+        line_buffering=sys.stderr.line_buffering,
+    )
+
 httpserver = util.httpserver
 socketserver = util.socketserver
 urlreq = util.urlreq