PHP sprintf() Function

PHP sprintf() Function

❮ PHP String Reference


Replace the percent (%) sign by a variable passed as an argument:

$number = 9;
$str = "Beijing";
$txt = sprintf("There are %u million bicycles in %s.",$number,$str);
echo $txt;
Run example »

Definition and Usage

The sprintf() function writes a formatted string to a variable.

The arg1, arg2, ++ parameters will be inserted at percent (%) signs in the main string. This function works "step-by-step". At the first % sign, arg1 is inserted, at the second % sign, arg2 is inserted, etc.

Note: If there are more % signs than arguments, you must use placeholders. A placeholder is inserted after the % sign, and consists of the argument- number and "\$". See example two.

Tip: Related functions: printf(), vprintf(), vsprintf(), fprintf() and vfprintf()



Parameter Description
format Required. Specifies the string and how to format the variables in it.

Possible format values:

  • %% - Returns a percent sign
  • %b - Binary number
  • %c - The character according to the ASCII value
  • %d - Signed decimal number (negative, zero or positive)
  • %e - Scientific notation using a lowercase (e.g. 1.2e+2)
  • %E - Scientific notation using a uppercase (e.g. 1.2E+2)
  • %u - Unsigned decimal number (equal to or greather than zero)
  • %f - Floating-point number (local settings aware)
  • %F - Floating-point number (not local settings aware)
  • %g - shorter of %e and %f
  • %G - shorter of %E and %f
  • %o - Octal number
  • %s - String
  • %x - Hexadecimal number (lowercase letters)
  • %X - Hexadecimal number (uppercase letters)

Additional format values. These are placed between the % and the letter (example %.2f):

  • + (Forces both + and - in front of numbers. By default, only negative numbers are marked)
  • ' (Specifies what to use as padding. Default is space. Must be used together with the width specifier. Example: %'x20s (this uses "x" as padding)
  • - (Left-justifies the variable value)
  • [0-9] (Specifies the minimum width held of to the variable value)
  • .[0-9] (Specifies the number of decimal digits or maximum string length)

Note: If multiple additional format values are used, they must be in the same order as above.

arg1 Required. The argument to be inserted at the first %-sign in the format string
arg2 Optional. The argument to be inserted at the second %-sign in the format string
arg++ Optional. The argument to be inserted at the third, fourth, etc. %-sign in the format string

Technical Details

Return Value: Returns the formatted string
PHP Version: 4+

More Examples

Example 1

Using the format value %f:

$number = 123;
$txt = sprintf("%f",$number);
echo $txt;
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Example 2

Use of placeholders:

$number = 123;
$txt = sprintf("With 2 decimals: %1\$.2f
<br>With no decimals: %1\$u",$number);
echo $txt;
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Example 3

A demonstration of all possible format values:

$num1 = 123456789;
$num2 = -123456789;
$char = 50; // The ASCII Character 50 is 2

// Note: The format value "%%" returns a percent sign
echo sprintf("%%b = %b",$num1)."<br>"; // Binary number
echo sprintf("%%c = %c",$char)."<br>"; // The ASCII Character
echo sprintf("%%d = %d",$num1)."<br>"; // Signed decimal number
echo sprintf("%%d = %d",$num2)."<br>"; // Signed decimal number
echo sprintf("%%e = %e",$num1)."<br>"; // Scientific notation (lowercase)
echo sprintf("%%E = %E",$num1)."<br>"; // Scientific notation (uppercase)
echo sprintf("%%u = %u",$num1)."<br>"; // Unsigned decimal number (positive)
echo sprintf("%%u = %u",$num2)."<br>"; // Unsigned decimal number (negative)
echo sprintf("%%f = %f",$num1)."<br>"; // Floating-point number (local settings aware)
echo sprintf("%%F = %F",$num1)."<br>"; // Floating-point number (not local sett aware)
echo sprintf("%%g = %g",$num1)."<br>"; // Shorter of %e and %f
echo sprintf("%%G = %G",$num1)."<br>"; // Shorter of %E and %f
echo sprintf("%%o = %o",$num1)."<br>"; // Octal number
echo sprintf("%%s = %s",$num1)."<br>"; // String
echo sprintf("%%x = %x",$num1)."<br>"; // Hexadecimal number (lowercase)
echo sprintf("%%X = %X",$num1)."<br>"; // Hexadecimal number (uppercase)
echo sprintf("%%+d = %+d",$num1)."<br>"; // Sign specifier (positive)
echo sprintf("%%+d = %+d",$num2)."<br>"; // Sign specifier (negative)
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Example 4

A demonstration of string specifiers:

$str1 = "Hello";
$str2 = "Hello world!";

echo sprintf("[%s]",$str1)."<br>";
echo sprintf("[%8s]",$str1)."<br>";
echo sprintf("[%-8s]",$str1)."<br>";
echo sprintf("[%08s]",$str1)."<br>";
echo sprintf("[%'*8s]",$str1)."<br>";
echo sprintf("[%8.8s]",$str2)."<br>";
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❮ PHP String Reference