Show a number to two decimal places

Question

What's the correct way to round a PHP string to two decimal places?

$number = "520"; // It's a string from a database

$formatted_number = round_to_2dp($number);

echo $formatted_number;

The output should be 520.00;

How should the round_to_2dp() function definition be?

Answer 1

Here I get two decimals after the . (dot) using a function...

function truncate_number($number, $precision = 2) {

    // Zero causes issues, and no need to truncate
    if (0 == (int)$number) {
        return $number;
    }

    // Are we negative?
    $negative = $number / abs($number);

    // Cast the number to a positive to solve rounding
    $number = abs($number);

    // Calculate precision number for dividing / multiplying
    $precision = pow(10, $precision);

    // Run the math, re-applying the negative value to ensure
    // returns correctly negative / positive
    return floor( $number * $precision ) / $precision * $negative;
}

Results from the above function:

echo truncate_number(2.56789, 1); // 2.5
echo truncate_number(2.56789);    // 2.56
echo truncate_number(2.56789, 3); // 2.567

echo truncate_number(-2.56789, 1); // -2.5
echo truncate_number(-2.56789);    // -2.56
echo truncate_number(-2.56789, 3); // -2.567

New Correct Answer

Use the PHP native BC Math function bcdiv

echo bcdiv(2.56789, 1, 1);  // 2.5
echo bcdiv(2.56789, 1, 2);  // 2.56
echo bcdiv(2.56789, 1, 3);  // 2.567
echo bcdiv(-2.56789, 1, 1); // -2.5
echo bcdiv(-2.56789, 1, 2); // -2.56
echo bcdiv(-2.56789, 1, 3); // -2.567

Answer 2

That's the same question I came across today and want to round a number and return float value up to a given decimal place and it must not be string (as returned from number_format) the answer is

printf('%.' . $decimalPlaces . 'f', round($number, $decimalPlaces));

thanks to mickmackusa for indicating the mistake

Answer 3

use round(yourValue,decimalPoint) (php manual’s page) or number_format(yourValue,decimalPoint);

number_format() return value as string like this type 1,234.67. so in this case you can not use it for addition or any calculation. if you try then you have to deal with Number Format Error...

In this case round(121222.299000000,2) will be better option. The result would be 121222.29 ...

Answer 4

• Choose the number of decimals
• Format commas(,)
• An option to trim trailing zeros

Once and for all!

function format_number($number,$dec=0,$trim=false){
  if($trim){
    $parts = explode(".",(round($number,$dec) * 1));
    $dec = isset($parts[1]) ? strlen($parts[1]) : 0;
  }
  $formatted = number_format($number,$dec); 
  return $formatted;
}

Examples

echo format_number(1234.5,2,true); //returns 1,234.5
echo format_number(1234.5,2);      //returns 1,234.50
echo format_number(1234.5);        //returns 1,235

Answer 5

Adding to other answers, since number_format() will, by default, add thousands separator.

To remove this, do this:

$number = number_format($number, 2, ".", "");

Answer 6

Use round() (use if you are expecting a number in float format only, else use number_format() as an answer given by Codemwnci):

echo round(520.34345, 2);   // 520.34
echo round(520.3, 2);       // 520.3
echo round(520, 2);         // 520

From the manual:

Description:

float round(float $val [, int $precision = 0 [, int $mode = PHP_ROUND_HALF_UP ]]);

Returns the rounded value of val to specified precision (number of digits after the decimal point). precision can also be negative or zero (default).

...

Example #1 round() examples

<?php
    echo round(3.4);         // 3
    echo round(3.5);         // 4
    echo round(3.6);         // 4
    echo round(3.6, 0);      // 4
    echo round(1.95583, 2);  // 1.96
    echo round(1241757, -3); // 1242000
    echo round(5.045, 2);    // 5.05
    echo round(5.055, 2);    // 5.06
?>

###Example #2 mode examples

<?php
    echo round(9.5, 0, PHP_ROUND_HALF_UP);   // 10
    echo round(9.5, 0, PHP_ROUND_HALF_DOWN); // 9
    echo round(9.5, 0, PHP_ROUND_HALF_EVEN); // 10
    echo round(9.5, 0, PHP_ROUND_HALF_ODD);  // 9

    echo round(8.5, 0, PHP_ROUND_HALF_UP);   // 9
    echo round(8.5, 0, PHP_ROUND_HALF_DOWN); // 8
    echo round(8.5, 0, PHP_ROUND_HALF_EVEN); // 8
    echo round(8.5, 0, PHP_ROUND_HALF_ODD);  // 9
?>

Answer 7

Here's another solution with strtok and str_pad:

$num = 520.00
strtok(round($num, 2), '.') . '.' . str_pad(strtok('.'), 2, '0')

Answer 8

Use the PHP number_format() function.

For example,

$num = 7234545423;
echo number_format($num, 2);

The output will be:

7,234,545,423.00

Answer 9

If you want to use two decimal digits in your entire project, you can define:

bcscale(2);

Then the following function will produce your desired result:

$myvalue = 10.165445;
echo bcadd(0, $myvalue);
// result=10.11

But if you don't use the bcscale function, you need to write the code as follows to get your desired result.

$myvalue = 10.165445;
echo bcadd(0, $myvalue, 2);
// result=10.11

To know more

• BC Math Functions

• bcscale

Answer 10

bcdiv($number, 1, 2) // 2 varies for digits after the decimal point

This will display exactly two digits after the decimal point.

Advantage:

If you want to display two digits after a float value only and not for int, then use this.

Answer 11

Number without round

$double = '21.188624';
echo intval($double) . '.' . substr(end(explode('.', $double)), 0, 2);

Answer 12

You can use the PHP printf or sprintf functions:

Example with sprintf:

$num = 2.12;
echo sprintf("%.3f", $num);

You can run the same without echo as well. Example: sprintf("%.3f", $num);

Output:

2.120

Alternatively, with printf:

echo printf("%.2f", $num);

Output:

2.124

Answer 13

I make my own.

$decimals = 2;
$number = 221.12345;
$number = $number * pow(10, $decimals);
$number = intval($number);
$number = $number / pow(10, $decimals);

Answer 14

round_to_2dp is a user-defined function, and nothing can be done unless you posted the declaration of that function.

However, my guess is doing this: number_format($number, 2);

Answer 15

Use the PHP number_format() function.

Answer 16

For conditional rounding off ie. show decimal where it's really needed otherwise whole number

123.56 => 12.56

123.00 => 123

$somenumber = 123.56;

$somenumber = round($somenumber,2);

if($somenumber == intval($somenumber))
{
    $somenumber = intval($somenumber);
}

echo $somenumber; // 123.56


$somenumber = 123.00;

$somenumber = round($somenumber,2);

if($somenumber == intval($somenumber))
{
    $somenumber = intval($somenumber);
}

echo $somenumber; // 123    

Answer 17

Another more exotic way to solve this issue is to use bcadd() with a dummy value for the $right_operand of 0.

$formatted_number = bcadd($number, 0, 2);

Answer 18

$retailPrice = 5.989;
echo number_format(floor($retailPrice*100)/100,2, '.', ''); 

It will return 5.98 without rounding the number.

Answer 19

$twoDecNum = sprintf('%0.2f', round($number, 2));

The rounding correctly rounds the number and the sprintf forces it to 2 decimal places if it happens to to be only 1 decimal place after rounding.

Answer 20

$number = sprintf('%0.2f', $numbers); // 520.89898989 -> 520.89

This will give you 2 number after decimal.

Answer 21

http://php.net/manual/en/function.round.php

e.g.

echo round(5.045, 2);    // 5.05

echo round(5.055, 2);    // 5.06

Answer 22

You can use number_format():

return number_format((float)$number, 2, '.', '');

Example:

$foo = "105";
echo number_format((float)$foo, 2, '.', '');  // Outputs -> 105.00

This function returns a string.

Answer 23

Try:

$number = 1234545454; 
echo  $english_format_number = number_format($number, 2); 

The output will be:

1,234,545,454.00

Answer 24

Alternatively,

$padded = sprintf('%0.2f', $unpadded); // 520 -> 520.00