Show current date and time in javascript

At the very least you should change

da+=endings[dayendings[da]]; 

to

da+=endings[dayendings[da - 1]]; 

because right now it has an off-by-one bug (da is 1 to 31, but the indexes on dayendings are 0 to 30).

This should immediately fix your problem if "today" is the 31st of the month.

Fixes are also needed for the values in dayendings, as 4 is not meaningful there.

On a side note, you really should ditch this code for something better. Wouldn't you prefer it like this?

function startTime() { document.getElementById("time").innerHTML = moment().format("dddd, MMMM Do, YYYY h:mm:ss A"); } 

Your var dayendings=[0,1,2,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,4,0,2,3,4,4,4,4,4,4,1]; includes some 4 values. Yet, var endings=["st","nd","rd","th"]; has only a length of 4, so that it will return undefined when you access endings[4].

Also, you may get an off-by-one-error because da is in the range 1 to 31, which are not the indizes of your dayendings array.

It appears that your logic for the counter is not correct. Try the following code:

function makeArray() { for (i = 0; i<makeArray.arguments.length; i++) this[i + 1] = makeArray.arguments[i]; } var now = new Date(); var h=now.getHours(); var min=now.getMinutes(); var s=now.getSeconds(); var ampm=(now.getHours()>11)?"PM":"AM"; var months = new makeArray('January','February','March','April','May', 'June','July','August','September','October','November','December'); var date = new Date(); var day = date.getDate(); var month = date.getMonth() + 1; var yy = date.getYear(); var year = (yy < 1000) ? yy + 1900 : yy; var endings=["st","nd","rd","th"]; var dayendings=[0,1,2,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,4,0,2,3,4,4,4,4,4,4,1]; var days=["Sunday","Monday","Tuesday","Wednesday","Thursday","Friday","Saturday","Sunday"]; document.write(days[date.getDay()] + " " + months[month]+ " " + day + ", " + year + " " + h + ":" + min + ":" + s + " " + ampm); 

I've a relatively simple DateTime object in this jsfiddle. May be useful? In your case, using this object, this command would show the date in the format you want (apart from the PM/AM time formatting)

XDate({date:new Date,lang:'EN'}).format('WD, MM dd, yyyy, hh:mm:se0'); //=> Friday, May 25 2012, 13:05:03 

first generate this function and save as .js file

function date_time(id) { date = new Date; year = date.getFullYear(); month = date.getMonth(); months = new Array('January', 'February', 'March', 'April', 'May', 'June', 'Jully', 'August', 'September', 'October', 'November', 'December'); d = date.getDate(); day = date.getDay(); days = new Array('Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday'); h = date.getHours(); if (h < 10) { h = "0" + h; } m = date.getMinutes(); if (m < 10) { m = "0" + m; } s = date.getSeconds(); if (s < 10) { s = "0" + s; } result = '' + days[day] + ' ' + months[month] + ' ' + d + ' ' + year + ' ' + h + ':' + m + ':' + s; document.getElementById(id).innerHTML = result; setTimeout('date_time("' + id + '");', '1000'); return true; } 

then use this code on your html page to display the current time and date

<script type="text/javascript"> window.onload = date_time('date_time'); </script> 

dont forget the script tag on the head part of your page: ex