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Go (Golang) Data Types

Go is a statically typed language, meaning variables must have a defined type at compile time.

Type	Description	Size (bits)	Range/Example
`int` ⬇️	Signed integer (platform-dependent)	32 or 64	`-2³¹` to `2³¹-1` (32-bit)
`int8`	8-bit signed integer	8	`-128` to `127`
`int16`	16-bit signed integer	16	`-32768` to `32767`
`int32`	32-bit signed integer	32	`-2³¹` to `2³¹-1`
`int64`	64-bit signed integer	64	`-2⁶³` to `2⁶³-1`
`uint` ⬇️	Unsigned integer (platform-dependent)	32 or 64	`0` to `2³²-1` (32-bit)
`uint8` (byte)⭐	8-bit unsigned integer	8	`0` to `255`
`uint16`	16-bit unsigned integer	16	`0` to `65535`
`uint32`	32-bit unsigned integer	32	`0` to `2³²-1`
`uint64`	64-bit unsigned integer	64	`0` to `2⁶⁴-1`
`float32`⬇️	32-bit floating-point	32	`±1.18e⁻³⁸` to `±3.4e³⁸`
`float64`⬇️	64-bit floating-point	64	`±2.23e⁻³⁰⁸` to `±1.8e³⁰⁸`
`bool`	Boolean (`true/false`)	8	`var flag bool = true`
`string`	Immutable UTF-8 text	-	`s := "Hello, Go!"`
`Rune⭐`	Alias for `int32` (Unicode code point)	32	`var r rune = 'A'`

Golang Formatting Verbs

Verb	Description	Example Types	Example Input	Example Output
`%v`	Default format	any	`Person{"John",25}`	`{John 25}`
`%+v`	Struct fields with names	structs	`Person{"John",25}`	`{Name:John Age:25}`
`%#v`	Go syntax representation	any	`Person{"John",25}`	`main.Person{Name:"John"}`
`%T⭐`	Type of the value	any	`"hello"`	`string`
`%%`	Literal percent sign	-	`"%%"`	`%`
`%t`	Boolean	bool	`true`	`true`
`%d`	Base-10 integer	integers	`42`	`42`
`%b`	Base-2 (binary)	integers	`42`	`101010`
`%o`	Base-8 (octal)	integers	`42`	`52`
`%x`	Base-16 (hex), lowercase	integers	`42`	`2a`
`%X`	Base-16 (hex), uppercase	integers	`42`	`2A`
`%f`	Decimal point, no exponent	floats	`3.14159265`	`3.141593`
`%e`	Scientific notation (e)	floats	`3.14159265`	`3.141593e+00`
`%E`	Scientific notation (E)	floats	`3.14159265`	`3.141593E+00`
`%g`	%e or %f, whichever is more compact	floats	`3.14159265`	`3.141592653589793`
`%G`	%E or %f, whichever is more compact	floats	`3.14159265`	`3.141592653589793`
`%s`	Plain string	strings	`"hello"`	`hello`
`%q`	Quoted string	strings	`"hello"`	`"hello"`
`%p`	Pointer address	pointers	`&x`	`0xc000010050`
`%c⭐`	Unicode character	runes	`65`	`A`
`%U`	Unicode format (U+1234)	runes	`65`	`U+0041`

General Verbs


  type Person struct {
  	name string
  	age  int
  }
 
  // %v: The "default" format. For structs, this shows field values without names.
  fmt.Printf("%v", person) // {John 25}
 
  // %+v: For structs, includes field names.
  fmt.Printf("%+v", person) // {Name:John Age:25}
 
  // %#v: Go-syntax representation of the value.
  fmt.Printf("%#v", person) // main.Person{Name:"John", Age:25}
 
  //%T: Prints the type of a value.
  fmt.Printf("%T", "hello") // string


// Integer Formatting
n := 42
fmt.Printf("%d %b %o %x %X", n, n, n, n, n)
// Output: 42 101010 52 2a 2A
 
// Float Formatting
pi := math.Pi
fmt.Printf("%f %.2f %e %E %g %G", pi, pi, pi, pi, pi, pi)
// Output: 3.141593 3.14 3.141593e+00 3.141593E+00 3.141592653589793 3.141592653589793
 
// String and Rune Formatting
s := "hello"
r := 'A'
fmt.Printf("%s %q %c %U", s, s, r, r)
// Output: hello "hello" A U+0041
 
// Special Cases
fmt.Printf("%%")  // Prints literal %
fmt.Printf("%t", true)  // Prints boolean