//secondsToTime();
            var t = wachttijd_sec; // your seconds
            var hour = Math.floor(t/3600);
            if(hour < 10){
                hour = '0'+hour;
            }
            var time = hour+':'+('0'+Math.floor(t/60)%60).slice(-2)+':'+('0' + t % 60).slice(-2);
            //would output: 00:00:00 > +100:00:00

即使超过24小时也能保持倒计时

我推荐使用普通的javascript，使用Date对象。(要获得更简短的解决方案，请使用toTimeString，请参阅第二个代码片段。)

var seconds = 9999;
// multiply by 1000 because Date() requires miliseconds
var date = new Date(seconds * 1000);
var hh = date.getUTCHours();
var mm = date.getUTCMinutes();
var ss = date.getSeconds();
// If you were building a timestamp instead of a duration, you would uncomment the following line to get 12-hour (not 24) time
// if (hh > 12) {hh = hh % 12;}
// These lines ensure you have two-digits
if (hh < 10) {hh = "0"+hh;}
if (mm < 10) {mm = "0"+mm;}
if (ss < 10) {ss = "0"+ss;}
// This formats your string to HH:MM:SS
var t = hh+":"+mm+":"+ss;
document.write(t);

(当然，创建的Date对象将有一个与之关联的实际日期，但该数据是无关的，因此出于这些目的，您不必担心它。)

编辑(简短的解决方案):

使用toTimeString函数并对空白进行分割:

var seconds = 9999; // Some arbitrary value
var date = new Date(seconds * 1000); // multiply by 1000 because Date() requires miliseconds
var timeStr = date.toTimeString().split(' ')[0];

toTimeString给出'16:54:58 GMT-0800 (PST)'，对第一个空格进行分割给出'16:54:58'。

我会给artem的答案投票，但我是一个新海报。我确实扩展了他的解决方案，虽然不是OP要求的如下

    t=(new Date()).toString().split(" ");
    timestring = (t[2]+t[1]+' <b>'+t[4]+'</b> '+t[6][1]+t[7][0]+t[8][0]);

得到

0410月16:31:28太平洋时间

这对我很有用……

但如果你从一个时间量开始，我会用两个函数;一个用于格式化和填充，一个用于计算:

function sec2hms(timect){

  if(timect=== undefined||timect==0||timect === null){return ''};
  //timect is seconds, NOT milliseconds
  var se=timect % 60; //the remainder after div by 60
  timect = Math.floor(timect/60);
  var mi=timect % 60; //the remainder after div by 60
  timect = Math.floor(timect/60);
  var hr = timect % 24; //the remainder after div by 24
  var dy = Math.floor(timect/24);
  return padify (se, mi, hr, dy);
}

function padify (se, mi, hr, dy){
  hr = hr<10?"0"+hr:hr;
  mi = mi<10?"0"+mi:mi;
  se = se<10?"0"+se:se;
  dy = dy>0?dy+"d ":"";
  return dy+hr+":"+mi+":"+se;
}

以下是2019年更新的一句话:

//your date
var someDate = new Date("Wed Jun 26 2019 09:38:02 GMT+0100") 

var result = `${String(someDate.getHours()).padStart(2,"0")}:${String(someDate.getMinutes()).padStart(2,"0")}:${String(someDate.getSeconds()).padStart(2,"0")}`

//result will be "09:38:02"

我最喜欢Webjins的答案，所以我扩展了它以显示d后缀的日子，使显示有条件，并包括一个s后缀的普通秒:

function sec2str(t){
    var d = Math.floor(t/86400),
        h = ('0'+Math.floor(t/3600) % 24).slice(-2),
        m = ('0'+Math.floor(t/60)%60).slice(-2),
        s = ('0' + t % 60).slice(-2);
    return (d>0?d+'d ':'')+(h>0?h+':':'')+(m>0?m+':':'')+(t>60?s:s+'s');
}

返回"3d 16:32:12"或"16:32:12"或"32:12"或"12s"

毫秒到持续时间，简单的方法是:

// To have leading zero digits in strings.
function pad(num, size) {
    var s = num + "";
    while (s.length < size) s = "0" + s;
    return s;
}

// ms to time/duration
msToDuration = function(ms){
    var seconds = ms / 1000;
    var hh = Math.floor(seconds / 3600),
    mm = Math.floor(seconds / 60) % 60,
    ss = Math.floor(seconds) % 60,
    mss = ms % 1000;
    return pad(hh,2)+':'+pad(mm,2)+':'+pad(ss,2)+'.'+pad(mss,3);
}

它将327577转换为00:05:27.577。

更新

另一种不同场景的方法:

toHHMMSS = function (n) {
    var sep = ':',
        n = parseFloat(n),
        sss = parseInt((n % 1)*1000),
        hh = parseInt(n / 3600);
    n %= 3600;
    var mm = parseInt(n / 60),
        ss = parseInt(n % 60);
    return pad(hh,2)+sep+pad(mm,2)+sep+pad(ss,2)+'.'+pad(sss,3);
    function pad(num, size) {
        var str = num + "";
        while (str.length < size) str = "0" + str;
        return str;
    }
}

toHHMMSS(6315.077) // Return 01:45:15.077