A basic time difference calculator in google script js

In your Google Sheet, Click “Tools” and then choose “Script Editor“. Put the code given below. Don’t forget to use function in your result column as “=dodiff(cell1,cell2)

function dodiff(a, b) {
    if (a)
        a = fix(a);
    if (b)
        b = fix(b);
    if (Array.isArray(a) && Array.isArray(b)) {
        if (b[1] > a[1]) m = b[1] - a[1];
        else {
            m = b[1] - a[1] + 60;
            b[0]--;
        }
        if (b[0] >= a[0]) h = b[0] - a[0];
        else {
            h = b[0] - a[0] + 12;
        }
        m = m / 60;
        return (h + m).toPrecision(4);
    }
}

function fix(a) {
    if (a)
        x = a.toString().replace(" ", '').replace("am", "").replace("pm", "").replace("PM", "").replace("AM", "");
    x = x.split(":");
    x[0] = parseInt(x[0]);
    x[1] = parseInt(x[1]);
    return x;
}