diff --git a/aegisub/libaegisub/common/util.cpp b/aegisub/libaegisub/common/util.cpp
index 3b23a562d..f925e309c 100644
--- a/aegisub/libaegisub/common/util.cpp
+++ b/aegisub/libaegisub/common/util.cpp
@@ -19,9 +19,15 @@
 /// @ingroup libaegisub
 
 #ifndef LAGI_PRE
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <errno.h>
+
+#include <climits>
+#include <locale>
 #endif
 
-#include <locale>
 
 #include "libaegisub/util.h"
 
@@ -35,5 +41,17 @@ void str_lower(std::string &str) {
 	}
 }
 
+int strtoi(std::string &str) {
+	long l = strtol(str.c_str(), NULL, 10);
+
+	if (errno == ERANGE)
+		throw("Cannot convert to long (invalid range)");
+
+	if ((l < INT_MIN) || (l > INT_MAX))
+		throw("Cannot convert to int (invalid range)");
+
+	return (int)l;
+}
+
 	} // namespace util
 } // namespace agi
diff --git a/aegisub/libaegisub/include/libaegisub/util.h b/aegisub/libaegisub/include/libaegisub/util.h
index 13ddefe95..fd0600224 100644
--- a/aegisub/libaegisub/include/libaegisub/util.h
+++ b/aegisub/libaegisub/include/libaegisub/util.h
@@ -38,6 +38,7 @@ namespace agi {
 	void Rename(const std::string& from, const std::string& to);
 	void time_log(agi_timeval &tv);
 	void str_lower(std::string &str);
+	int strtoi(std::string &str);
 
 	struct delete_ptr {
 		template<class T>
diff --git a/aegisub/tests/libaegisub_util.cpp b/aegisub/tests/libaegisub_util.cpp
index 8a8ee59cc..49e5feb7e 100644
--- a/aegisub/tests/libaegisub_util.cpp
+++ b/aegisub/tests/libaegisub_util.cpp
@@ -71,5 +71,33 @@ TEST_F(lagi_util, Utilstr_lower) {
 	EXPECT_STREQ(str.c_str(), "-!abcdefghijklmnopqrstuvwxyz123");
 }
 
+TEST_F(lagi_util, UtilstrtoiInvalidRange) {
+	std::string str("2147483650");
+	EXPECT_ANY_THROW(util::strtoi(str));
+
+	str.assign("-2147483650");
+	EXPECT_ANY_THROW(util::strtoi(str));
+}
+
+TEST_F(lagi_util, UtilstrtoiInvalidString) {
+	std::string str("bottles of beer on the wall");
+	EXPECT_EQ(util::strtoi(str), 0);
+}
+
+TEST_F(lagi_util, UtilstrtoiNumberWithString) {
+	std::string str("24 bottles of beer on the wall");
+	EXPECT_EQ(util::strtoi(str), 24);
+}
+
+TEST_F(lagi_util, UtilstrtoiValidString) {
+	std::string str("24");
+	int i;
+
+	EXPECT_NO_THROW(i = util::strtoi(str));
+	EXPECT_EQ(i, 24);
+}
+
+
+
 
 } // namespace agi