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Data Type Ranges

Visual C++ 32-bit and 64-bit compilers recognize the types in the table later in this article.

  • int (unsignedint)

  • __int8 (unsigned__int8)

  • __int16 (unsigned__int16)

  • __int32 (unsigned__int32)

  • __int64 (unsigned__int64)

  • short (unsignedshort)

  • long (unsignedlong)

  • longlong (unsignedlonglong)

If its name begins with two underscores (__), a data type is non-standard.

The ranges that are specified in the following table are inclusive-inclusive.

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 by using /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 later in this article

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

Depending on how it's used, a variable of __wchar_t designates either a wide-character type or multibyte-character type. Use the L prefix before a character or string constant to designate the wide-character-type constant.

signed and unsigned are modifiers that you can use with any integral type except bool. Note that char, signed char, and unsigned char are three distinct types for the purposes of mechanisms like overloading and templates.

The int and unsignedint types have a size of four bytes. However, portable code should not depend on the size of int because the language standard allows this to be implementation-specific.

C/C++ in Visual Studio also supports sized integer types. For more information, see __int8, __int16, __int32, __int64 and Integer Limits.

For more information about the restrictions of the sizes of each type, see Fundamental Types (C++).

The range of enumerated types varies depending on the language context and specified compiler flags. For more information, see C Enumeration Declarations and C++ Enumeration Declarations.

See Also

Reference

C++ Keywords

Fundamental Types (C++)