diff --git a/src/utils.cpp b/src/utils.cpp
index ddda61e..3b1426c 100644
--- a/src/utils.cpp
+++ b/src/utils.cpp
@@ -36,3 +36,8 @@ std::vector<std::string> strsplit(const std::string& str, const std::string& del
 	r.push_back(str.substr(s));
 	return r;
 }
+
+void strtolower(std::string& str) {
+
+	std::transform(str.begin(), str.end(), str.begin(), [](unsigned char c){ return std::tolower(c); });
+}
diff --git a/src/utils.h b/src/utils.h
index ad3d4c2..120bf7c 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -29,4 +29,6 @@
 
 std::vector<std::string> strsplit(const std::string& str, const std::string& delim);
 
+void strtolower(std::string& str);
+
 #endif /* UTILS_H */