Javascript library for human-friendly relative date formatting

Question

I'd like to display some dates as relative to the current date in a human-friendly format.

Examples of human-friendly relative dates:

• 10 seconds ago
• 20 minutes from now
• 1 day ago
• 5 weeks ago
• 2 months ago

Basically faithfully preserving the highest order of magnitude (and by preference, only shifting up units when passing 2 of those units - 5 weeks instead of 1 month).

Though I could live with a library that had less control and even more friendly dates like:

• yesterday
• tomorrow
• last week
• a few minutes ago
• in a couple hours

Any popular libraries for this?

Answer 1

Since I wrote this answer, a well known library available is moment.js.

---

There are libraries available, but it is trivial to implement it yourself. Just use a handful of conditions.

Assume date is an instantiated Date object for the time you want to make a comparison against.

// Make a fuzzy time
var delta = Math.round((+new Date - date) / 1000);

var minute = 60,
    hour = minute * 60,
    day = hour * 24,
    week = day * 7;

var fuzzy;

if (delta < 30) {
    fuzzy = 'just then.';
} else if (delta < minute) {
    fuzzy = delta + ' seconds ago.';
} else if (delta < 2 * minute) {
    fuzzy = 'a minute ago.'
} else if (delta < hour) {
    fuzzy = Math.floor(delta / minute) + ' minutes ago.';
} else if (Math.floor(delta / hour) == 1) {
    fuzzy = '1 hour ago.'
} else if (delta < day) {
    fuzzy = Math.floor(delta / hour) + ' hours ago.';
} else if (delta < day * 2) {
    fuzzy = 'yesterday';
}

You would need to adapt this to handle future dates.