#27. Kevin on 15 February 2009

@ Rival: Hey there, excellent work Rival! I've also added 2 test cases that cover your findings so we can't make that mistake again. Thanks!

#26. Rival on 12 February 2009

cleanup

....
    var abs = Math.abs(s);
....

#25. Rival on 12 February 2009

- show thousand separator for number=1000
- decimal point for numbers lower than 1000 is undefined

note: for 1000.55 result with precision 1 in FF/Opera is 1,000.5, but in IE is 1,000.6

function number_format(number, decimals, dec_point, thousands_sep) {
    var n = number, prec = decimals;
    n = !isFinite(+n) ? 0 : +n;
    prec = !isFinite(+prec) ? 0 : Math.abs(prec);
    var sep = (typeof thousands_sep == "undefined") ? ',' : thousands_sep;
    var dec = (typeof dec_point == "undefined") ? '.' : dec_point;
 
    var s = (prec > 0) ? n.toFixed(prec) : Math.round(n).toFixed(prec); //fix for IE parseFloat(0.55).toFixed(0) = 0;
 
    var abs = Math.abs(n).toFixed(prec);
    var _, i;
 
    if (abs >= 1000) {
        _ = abs.split(/\D/);
        i = _[0].length % 3 || 3;
 
        _[0] = s.slice(0,i + (n < 0)) +
              _[0].slice(i).replace(/(\d{3})/g, sep+'$1');
 
        s = _.join(dec);
    } else {
        s = s.replace('.', dec);
    }
 
    return s;
}

#24. Kevin on 02 February 2009

@ Diogo Resende: Confirmed. I've processed your fix. Thanks a lot!

#23. Diogo Resende on 02 February 2009

Sorry, the correct code is:

s = abs.replace('.', dec_point);

#22. Diogo Resende on 02 February 2009

It's not correct for numbers below 1000. It needs an else statement like this:

if (abs > 1000) {
...
} else {
  s = abs.replace('.', ',');
}

#21. Kevin on 16 January 2009

@ Luke: After I changed:

prec = !isFinite(+prec) ? 2 : Math.abs(prec);

To

prec = !isFinite(+prec) ? 0 : Math.abs(prec);

..All test cases from the php manual worked perfectly. And since your code is a bit easier on the eyes as well, I'll include it in our project. Thanks a lot!

#20. Luke on 16 January 2009

I attacked the same problem recently and came up with a similar solution
http://gist.github.com/47871

more lines, but fewer characters, and compresses (via YUI Compressor) to about 83% of the version above. Take a look; there may be improvements to be made.

#19. Memiux on 15 January 2009

Thanks, It's so beautiful and tiny :)

#18. Cees on 14 January 2009

This was so what I was looking for!!! Thanks, guys!!!

#17. Mariusz on 04 November 2008

I take it back, got the latest version and all looks good. Thanks to those involved with the fixes!

#16. Mariusz on 04 November 2008

This method does not seem to work correctly with negative numbers, for example (to 2 decimal places):

-16038 returns: -160,38.00

-820 returns -,820.00

#15. Chad Smith on 28 August 2008

Ignore my previous comment, I'm an idiot. I was checking to see if it was larger than 1000 before it ran through the function. Duh, sorry.

Love the script!
Chad

#14. Chad Smith on 28 August 2008

Anyone else notice that if you just put in 1000 it doesn't format the number to 1,000? But if you put in 1001 it formats correctly to 1,001.

Any idea what could make that happen?

#13. Kevin on 08 June 2008

@ Howard Yeend: Thanks for noticing. This function was revised, and that reimported a previously fixed bug. It's probably because in some countries (including my own), the dec_point and thou_sep are indeed the other way around compared to the english standard. Anyway. fixed again :)

#12. Howard Yeend on 06 June 2008

just a comment; aren't the default values for dec_point and thou_sep the wrong way around?

by default it formats 12345.67 as 12.345,67

shouldn't it be 12,345.67 ?

#11. Kevin on 13 April 2008

@ Jonas Raoni: Thanks I've updated the function. I have one remark though. We generally compress code with packer & jsmin to obtain bandwidth & speed advantages, while maintaining readability so developers can more easily understand and update each others code.

#10. Jonas Raoni on 12 April 2008

I corrected all of the bugs that I found:
- Negative numbers;
- Starting with zero;
- Rouding (when cutting the decimal places of "0.9" it should be 1 not 0).

... [more] And here is the last version of the code:

Number.prototype.formatMoney = function(c, d, t){
var n = this, c = isNaN(c = Math.abs(c)) ? 2 : c, d = d == undefined ? "," : d, t = t == undefined ? "." : t, s = n < 0 ? "-" : "",
i = parseInt(n = Math.abs(+n || 0).toFixed(c)) + "", j = (j = i.length) > 3 ? j % 3 : 0;
return s + (j ? i.substr(0, j) + t : "") + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + t)
+ (c ? d + Math.abs(n - i).toFixed(c).slice(2) : "");
};

#9. Howard Yeend on 09 April 2008

yay for Allan Jensen. I just noticed the same bug he fixed. cheers dude.

#8. Kevin on 29 March 2008

@ Allan Jensen: Wow thanks for fixing it!

#7. Allan Jensen on 28 March 2008

Fixed the problem with negative numbers myself. Function needs to look like this:

function number_format( number, decimals, dec_point, thousands_sep ) {
    // http://kevin.vanzonneveld.net
    // +   original by: Jonas Raoni Soares Silva (http://www.jsfromhell.com)
    // +   improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +     bugfix by: Michael White (http://crestidg.com)
    // +     bugfix by: Benjamin Lupton
  // +     bugfix by: Allan Jensen (http://www.winternet.no) (fixed formatting negative numbers)
    // *     example 1: number_format(1234.5678, 2, '.', '');
    // *     returns 1: 1234.57
 
    var i, j, kw, kd, km;
  var neg = "";
 
  // Input sanitation & defaults
  if ( isNaN(decimals = Math.abs(decimals)) ) {
    decimals = 2;
  }
  if (dec_point == undefined) {
    dec_point = ".";
  }
  if (thousands_sep == undefined) {
    thousands_sep = ",";
  }
 
  i = parseInt(number = (+number || 0).toFixed(decimals)) + "";
  if (i.substr(0,1) == "-") {
    number = Math.abs(number);
    neg = "-";
    i = i.substr(1);
  }
 
  if ((j = i.length) > 3 ) {
    j = j % 3;
  } else {
    j = 0;
  }
 
  km = (j ? i.substr(0, j) + thousands_sep : "");
  kw = i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + thousands_sep);
  //kd = (decimals ? dec_point + Math.abs(number - i).toFixed(decimals).slice(2) : "");
  kd = (decimals ? dec_point + Math.abs(number - i).toFixed(decimals).replace(/-/, 0).slice(2) : "");
  return neg + km + kw + kd;
}

#6. Allan Jensen on 28 March 2008

The function has a problem with negative numbers.

This:

number_format(-258.75, 2, ",", ".")
... [more]
incorrectly gives:

-,258,75

Please help me fix this.

#5. Kevin on 20 March 2008

@ Benjamin Lupton: Thank you!

#4. Benjamin &quot;balupton&quot; Lupton on 20 March 2008

dec_point and thousands_sep defaults should be the other way round

#3. Michael White on 01 March 2008

No problem. I love having these familiar PHP functions available. I have a sort of proposal for you, maybe you could contact me via email (michael -a-t- crestidg.com) so I can get you some more details. It probably wouldn't take too much time for us to do and it would benefit those who want to use the entire PHP.js package along side other JavaScript quite a lot.

#2. Kevin on 01 March 2008

@ Michael White: It sure did, thanks for taking the time to supply better code. I've updated the function!

#1. Michael White on 01 March 2008

There is a bug in Safari - at least in Safari 3.0.4 that causes the combination of Math.abs(0).toFixed(x) where x seems to be any positive integer to provide erroneous output.

The sample code below contains problematic code at the top and a sample solution line at the end. The new code for the number_format() function actually is in a separate code block below this one.

var price = 0.00;
alert(Math.abs(price)); // Alerts: 0 - correct.
  
// Alerts: 0.00 in most browsers.
// In Safari 3.0.4 you get: 0.-0
alert(Math.abs(price).toFixed(2));
  
// However - If you skip the use of Math.abs() on a 0 value then the toFixed() function works correctly.
var new_price = 0;
alert(new_price.toFixed(2));
  
// Temp-fix ( I submitted this bug to Apple)
var num = 0;
var result = Math.abs(0).toFixed(1);
alert(result);
result = result.replace(/-/, 0);
alert(result);

Since this problem only occurs when working on a value of 0 (zero) to begin with we know that the hyphen character should be a 0 so we can simply replace it with a 0 if it is found.

// The easiest way to fix this is to simply modify the line that reads:
kd = (decimals ? dec_point + Math.abs(number - i).toFixed(decimals).slice(2) : "");
 
// with the following line of code:
kd = (decimals ? dec_point + Math.abs(number - i).toFixed(decimals).replace(/-/, 0).slice(2) : "");
 
// The only difference is the addition of .replace(/-/, 0) just before the slice() method is used.
// This tiny extra amount of processing should not be significant unless number_format() is run in very tight loops - and even then it can only be considered extra in browsers like IE, Opera, and Firefox since this appears to be a Safari only bug. Checking the browser seemed to be overkill in this instance.

I hope it helps!

Michael White - 2008
michael -a-t- crestidg.com
http://crestidg.com/