diff --git a/taglib/toolkit/tstring.cpp b/taglib/toolkit/tstring.cpp
index cca15e10..493a1dcd 100644
--- a/taglib/toolkit/tstring.cpp
+++ b/taglib/toolkit/tstring.cpp
@@ -515,12 +515,12 @@ bool String::isAscii() const
 
 String String::number(int n) // static
 {
-  return Utils::formatString("%d", n);
+  return std::to_string(n);
 }
 
 String String::fromLongLong(long long n) // static
 {
-  return Utils::formatString("%lld", n);
+  return std::to_string(n);
 }
 
 wchar_t &String::operator[](int i)