diff --git a/src/zstring.cpp b/src/zstring.cpp
index aed599cd6..cef956c90 100644
--- a/src/zstring.cpp
+++ b/src/zstring.cpp
@@ -696,7 +696,7 @@ void FString::StripRight ()
 {
 	size_t max = Len(), i;
 	if (max == 0) return;
-	for (i = --max; i-- > 0; )
+	for (i = --max; i > 0; i--)
 	{
 		if (!isspace((unsigned char)Chars[i]))
 			break;
@@ -728,12 +728,12 @@ void FString::StripRight (const char *charset)
 {
 	size_t max = Len(), i;
 	if (max == 0) return;
-	for (i = --max; i-- > 0; )
+	for (i = --max; i > 0; i--)
 	{
 		if (!strchr (charset, Chars[i]))
 			break;
 	}
-	if (i == max)
+	if (i == max-1)
 	{ // Nothing to strip.
 		return;
 	}