# Get the week number with JavaScript – update

Hey guys,

Just wanted to let you know that I have found a better way to find the week number with javascript for a date. I pulled this gem from the datejs source:

``````function getWeek (getdate) {
var a, b, c, d, e, f, g, n, s, w;

\$y = getdate.getFullYear();
\$m = getdate.getMonth() + 1;
\$d = getdate.getDate();

if (\$m <= 2) {
a = \$y - 1;
b = (a / 4 | 0) - (a / 100 | 0) + (a / 400 | 0);
c = ((a - 1) / 4 | 0) - ((a - 1) / 100 | 0) + ((a - 1) / 400 | 0);
s = b - c;
e = 0;
f = \$d - 1 + (31 * (\$m - 1));
} else {
a = \$y;
b = (a / 4 | 0) - (a / 100 | 0) + (a / 400 | 0);
c = ((a - 1) / 4 | 0) - ((a - 1) / 100 | 0) + ((a - 1) / 400 | 0);
s = b - c;
e = s + 1;
f = \$d + ((153 * (\$m - 3) + 2) / 5) + 58 + s;
}

g = (a + b) % 7;
d = (f + g - e) % 7;
n = (f + 3 - d) | 0;

if (n < 0) {
w = 53 - ((g - s) / 5 | 0);
} else if (n > 364 + s) {
w = 1;
} else {
w = (n / 7 | 0) + 1;
}

\$y = \$m = \$d = null;

return w;
}

weeknumber = getWeek(new Date());```
```

Now you have the correct week number with JavaScript!

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