< cpp‎ | types
Type support
Basic types
Fundamental types
Fixed width integer types (C++11)
Numeric limits
C numeric limits interface
Runtime type information
Type traits
Type categories
Type properties
(C++11)(until C++20)
(C++11)(deprecated in C++20)
Type trait constants
Constant evaluation context
Supported operations
Relationships and property queries
Type modifications
Type transformations
(C++11)(until C++20)(C++17)
Defined in header <type_traits>
template< class T >
struct make_unsigned;
(since C++11)

If T is an integral (except bool) or enumeration type, provides the member typedef type which is the unsigned integer type corresponding to T, with the same cv-qualifiers. The unsigned integer type corresponding to an enumeration type is the unsigned integer type with the smallest rank having the same sizeof as the enumeration.

Otherwise, the behavior is undefined.

Member types

Name Definition
type the unsigned integer type corresponding to T

Helper types

template< class T >
using make_unsigned_t = typename make_unsigned<T>::type;
(since C++14)


#include <iostream>
#include <type_traits>
int main() {
    typedef std::make_unsigned<char>::type char_type;
    typedef std::make_unsigned<int>::type int_type;
    typedef std::make_unsigned<volatile long>::type long_type;
    bool ok1 = std::is_same<char_type, unsigned char>::value; 
    bool ok2 = std::is_same<int_type, unsigned int>::value;
    bool ok3 = std::is_same<long_type, volatile unsigned long>::value;
    std::cout << std::boolalpha
    << "char_type is 'unsigned char'?          : " << ok1 << '\n'
    << "int_type  is 'unsigned int'?           : " << ok2 << '\n'
    << "long_type is 'volatile unsigned long'? : " << ok3 << '\n';


char_type is 'unsigned char'?          : true
int_type  is 'unsigned int'?           : true
long_type is 'volatile unsigned long'? : true

See also

checks if a type is a signed arithmetic type
(class template)
checks if a type is an unsigned arithmetic type
(class template)
makes the given integral type signed
(class template)