Data Type Ranges
For 32-bit and 64-bit compilers, Microsoft Visual C++ recognizes the types shown in the table below. Note that the following type also have unsigned forms:
int (unsigned int)
__int8 (unsigned __int8)
__int16 (unsigned __int16)
__int32 (unsigned __int32)
__int64 (unsigned __int64)
short (unsigned short)
long (unsigned long)
long long (unsigned long long)
Type Name |
Bytes |
Other Names |
Range of Values |
---|---|---|---|
int |
4 |
signed |
–2,147,483,648 to 2,147,483,647 |
unsigned int |
4 |
unsigned |
0 to 4,294,967,295 |
__int8 |
1 |
char |
–128 to 127 |
unsigned __int8 |
1 |
unsigned char |
0 to 255 |
__int16 |
2 |
short, short int, signed short int |
–32,768 to 32,767 |
unsigned __int16 |
2 |
unsigned short, unsigned short int |
0 to 65,535 |
__int32 |
4 |
signed, signed int, int |
–2,147,483,648 to 2,147,483,647 |
unsigned __int32 |
4 |
unsigned, unsigned int |
0 to 4,294,967,295 |
__int64 |
8 |
long long, signed long long |
–9,223,372,036,854,775,808 to 9,223,372,036,854,775,807 |
unsigned __int64 |
8 |
unsigned long long |
0 to 18,446,744,073,709,551,615 |
bool |
1 |
none |
false or true |
char |
1 |
none |
–128 to 127 by default 0 to 255 when compiled with /J |
signed char |
1 |
none |
–128 to 127 |
unsigned char |
1 |
none |
0 to 255 |
short |
2 |
short int, signed short int |
–32,768 to 32,767 |
unsigned short |
2 |
unsigned short int |
0 to 65,535 |
long |
4 |
long int, signed long int |
–2,147,483,648 to 2,147,483,647 |
unsigned long |
4 |
unsigned long int |
0 to 4,294,967,295 |
long long |
8 |
none (but equivalent to __int64) |
–9,223,372,036,854,775,808 to 9,223,372,036,854,775,807 |
unsigned long long |
8 |
none (but equivalent to unsigned __int64) |
0 to 18,446,744,073,709,551,615 |
enum |
varies |
none |
See Remarks. |
float |
4 |
none |
3.4E +/- 38 (7 digits) |
double |
8 |
none |
1.7E +/- 308 (15 digits) |
long double |
same as double |
none |
same as double |
wchar_t |
2 |
__wchar_t |
0 to 65,535 |
A variable of __wchar_t designates a wide-character or multibyte character type. By default wchar_t is a typedef for unsigned short. Use the L prefix before a character or string constant to designate the wide-character-type constant. When compiling with /Zc:wchar_t or /Za, the compiler can distinguish between an unsigned short and wchar_t for function overload purposes.
Signed and unsigned are modifiers that can be used with any integral type except bool. The char type behaves like signed char by default, but you can specify /J (compiler option) to make behave like unsigned char by default.
The int and unsigned int types have the size of the system word: four bytes. However, portable code should not depend on the size of int.
Microsoft C/C++ also features support for sized integer types. See __int8, __int16, __int32, __int64 for more information. Also see Integer Limits.
See Fundamental Types for more information on the restrictions of the sizes of each type.
The range of enumerated types varies depending on the language context and specified compiler flags. In C and C++ non-CLR enumerations, enumeration constants and values of enumerated types are expressed in terms of type int. C++ CLR enumerations may be backed by a specified scalar type. The range of an enumeration is defined as the smallest and largest values that can be stored in the bit-fields of the smallest and largest of its enumerators. However, the C++ compiler will allow any value within the range of the backing type of the enumeration to be specified (this may require a cast). For more information, refer to C Enumeration Declarations and C++ Enumeration Declarations.