Go Formatting Verbs

Formatting Verbs for Printf()

Go offers several formatting verbs that can be used with the Printf() function.

General Formatting Verbs

The following verbs can be used with all data types:

Verb	Description
%v	Prints the value in the default format
%#v	Prints the value in Go-syntax format
%T	Prints the type of the value
%%	Prints the % sign

Example

package main
import ("fmt")

func main() {
var i = 15.5
var txt = "Hello World!"

fmt.Printf("%v\n", i)
fmt.Printf("%#v\n", i)
fmt.Printf("%v%%\n", i)
fmt.Printf("%T\n", i)

fmt.Printf("%v\n", txt)
fmt.Printf("%#v\n", txt)
fmt.Printf("%T\n", txt)
}

Result:


      15.5
15.5
15.5%
float64
Hello World!
"Hello World!"

    string

Try it Yourself »

Integer Formatting Verbs

The following verbs can be used with the integer data type:

Verb	Description
%b	Base 2
%d	Base 10
%+d	Base 10 and always show sign
%o	Base 8
%O	Base 8, with leading 0o
%x	Base 16, lowercase
%X	Base 16, uppercase
%#x	Base 16, with leading 0x
%4d	Pad with spaces (width 4, right justified)
%-4d	Pad with spaces (width 4, left justified)
%04d	Pad with zeroes (width 4

Example

package main
import ("fmt")

func main() {
var i = 15

fmt.Printf("%b\n", i)
fmt.Printf("%d\n", i)
fmt.Printf("%+d\n", i)
fmt.Printf("%o\n", i)
fmt.Printf("%O\n", i)
fmt.Printf("%x\n", i)
fmt.Printf("%X\n", i)
fmt.Printf("%#x\n", i)
fmt.Printf("%4d\n", i)
fmt.Printf("%-4d\n", i)
fmt.Printf("%04d\n", i)
}

Result:

Try it Yourself »

String Formatting Verbs

The following verbs can be used with the string data type:

Verb	Description
%s	Prints the value as plain string
%q	Prints the value as a double-quoted string
%8s	Prints the value as plain string (width 8, right justified)
%-8s	Prints the value as plain string (width 8, left justified)
%x	Prints the value as hex dump of byte values
% x	Prints the value as hex dump with spaces

Example

package main
import ("fmt")

func main() {
var txt = "Hello"

fmt.Printf("%s\n", txt)
fmt.Printf("%q\n", txt)
fmt.Printf("%8s\n", txt)
fmt.Printf("%-8s\n", txt)
fmt.Printf("%x\n", txt)
fmt.Printf("% x\n", txt)
}

Result:


    Hello
"Hello"
   Hello
Hello 
48656c6c6f
48 65 6c 6c 6f

Try it Yourself »

Boolean Formatting Verbs

The following verb can be used with the boolean data type:

Verb	Description
%t	Value of the boolean operator in true or false format (same as using %v)

Example

package main
import ("fmt")

func main() {
var i = true
var j = false

fmt.Printf("%t\n", i)
fmt.Printf("%t\n", j)
}

Result:


      true
false

Try it Yourself »

Float Formatting Verbs

The following verbs can be used with the float data type:

Verb	Description
%e	Scientific notation with 'e' as exponent
%f	Decimal point, no exponent
%.2f	Default width, precision 2
%6.2f	Width 6, precision 2
%g	Exponent as needed, only necessary digits

Example

package main
import ("fmt")

func main() {
var i = 3.141

fmt.Printf("%e\n", i)
fmt.Printf("%f\n", i)
fmt.Printf("%.2f\n", i)
fmt.Printf("%6.2f\n", i)
fmt.Printf("%g\n", i)
}

Result:

3.141000e+00
3.141000
3.14
  3.14
3.141

Try it Yourself »

❮ Previous Next ❯