我的尝试是基于其他的答案。

function timeSince(date) {
    let minute = 60;
    let hour   = minute * 60;
    let day    = hour   * 24;
    let month  = day    * 30;
    let year   = day    * 365;

    let suffix = ' ago';

    let elapsed = Math.floor((Date.now() - date) / 1000);

    if (elapsed < minute) {
        return 'just now';
    }

    // get an array in the form of [number, string]
    let a = elapsed < hour  && [Math.floor(elapsed / minute), 'minute'] ||
            elapsed < day   && [Math.floor(elapsed / hour), 'hour']     ||
            elapsed < month && [Math.floor(elapsed / day), 'day']       ||
            elapsed < year  && [Math.floor(elapsed / month), 'month']   ||
            [Math.floor(elapsed / year), 'year'];

    // pluralise and append suffix
    return a[0] + ' ' + a[1] + (a[0] === 1 ? '' : 's') + suffix;
}

function calDateAgo(dString=null){
    //var dString = "2021-04-1 12:00:00";
     
    var d1 = new Date(dString);
    var d2 = new Date();
    var t2 = d2.getTime();
    var t1 = d1.getTime();
    var d1Y = d1.getFullYear();
    var d2Y = d2.getFullYear();
    var d1M = d1.getMonth();
    var d2M = d2.getMonth();
     
    var time_obj = {};
    time_obj.year = d2.getFullYear()-d1.getFullYear();
    time_obj.month = (d2M+12*d2Y)-(d1M+12*d1Y);
    time_obj.week = parseInt((t2-t1)/(24*3600*1000*7));
    time_obj.day = parseInt((t2-t1)/(24*3600*1000));
    time_obj.hour = parseInt((t2-t1)/(3600*1000));
    time_obj.minute = parseInt((t2-t1)/(60*1000));
    time_obj.second = parseInt((t2-t1)/(1000));

    for (const obj_key in time_obj) {
        if(time_obj[obj_key] == 0){
            delete time_obj[obj_key];
        }
    }
    var ago_text = 'just now';

    if(typeof Object.keys(time_obj)[0] != 'undefined'){
        var time_key = Object.keys(time_obj)[0];
        var time_val = time_obj[Object.keys(time_obj)[0]];
        time_key += (time_val > 1) ? 's':'';
        ago_text = time_val+' '+time_key+' ago'; 
    }
    
    return ago_text;
}

function timeago(date) {
    var seconds = Math.floor((new Date() - date) / 1000);
    if(Math.round(seconds/(60*60*24*365.25)) >= 2) return Math.round(seconds/(60*60*24*365.25)) + " years ago";
    else if(Math.round(seconds/(60*60*24*365.25)) >= 1) return "1 year ago";
    else if(Math.round(seconds/(60*60*24*30.4)) >= 2) return Math.round(seconds/(60*60*24*30.4)) + " months ago";
    else if(Math.round(seconds/(60*60*24*30.4)) >= 1) return "1 month ago";
    else if(Math.round(seconds/(60*60*24*7)) >= 2) return Math.round(seconds/(60*60*24*7)) + " weeks ago";
    else if(Math.round(seconds/(60*60*24*7)) >= 1) return "1 week ago";
    else if(Math.round(seconds/(60*60*24)) >= 2) return Math.round(seconds/(60*60*24)) + " days ago";
    else if(Math.round(seconds/(60*60*24)) >= 1) return "1 day ago";
    else if(Math.round(seconds/(60*60)) >= 2) return Math.round(seconds/(60*60)) + " hours ago";
    else if(Math.round(seconds/(60*60)) >= 1) return "1 hour ago";
    else if(Math.round(seconds/60) >= 2) return Math.round(seconds/60) + " minutes ago";
    else if(Math.round(seconds/60) >= 1) return "1 minute ago";
    else if(seconds >= 2)return seconds + " seconds ago";
    else return seconds + "1 second ago";
}

回答10年的老问题，帮助新人。

我们可以将这个包用于javascript时间之前

 
// Load locale-specific relative date/time formatting rules.
import en from 'javascript-time-ago/locale/en'
 
// Add locale-specific relative date/time formatting rules.
TimeAgo.addLocale(en)
 
// Create relative date/time formatter.
const timeAgo = new TimeAgo('en-US')
 
timeAgo.format(new Date())
// "just now"
 
timeAgo.format(Date.now() - 60 * 1000)
// "a minute ago"
 
timeAgo.format(Date.now() - 2 * 60 * 60 * 1000)
// "2 hours ago"
 
timeAgo.format(Date.now() - 24 * 60 * 60 * 1000)
// "a day ago"

这应该正确地处理任何有效的时间戳，包括Date.now()、单数单位和未来日期。我漏掉了月份，但是这些月份应该很容易加进去。我尽量保持它的可读性。

function getTimeInterval(date) { let seconds = Math.floor((Date.now() - date) / 1000); let unit = "second"; let direction = "ago"; if (seconds < 0) { seconds = -seconds; direction = "from now"; } let value = seconds; if (seconds >= 31536000) { value = Math.floor(seconds / 31536000); unit = "year"; } else if (seconds >= 86400) { value = Math.floor(seconds / 86400); unit = "day"; } else if (seconds >= 3600) { value = Math.floor(seconds / 3600); unit = "hour"; } else if (seconds >= 60) { value = Math.floor(seconds / 60); unit = "minute"; } if (value != 1) unit = unit + "s"; return value + " " + unit + " " + direction; } console.log(getTimeInterval(Date.now())); // 0 seconds ago console.log(getTimeInterval(Date.now() + 1000)); // 1 second from now console.log(getTimeInterval(Date.now() - 1000)); // 1 second ago console.log(getTimeInterval(Date.now() + 60000)); // 1 minute from now console.log(getTimeInterval(Date.now() - 120000)); // 2 minutes ago console.log(getTimeInterval(Date.now() + 120000)); // 2 minutes from now console.log(getTimeInterval(Date.now() + 3600000)); // 1 hour from now console.log(getTimeInterval(Date.now() + 360000000000)); // 11 years from now console.log(getTimeInterval(0)); // 49 years ago

在这种情况下可能有点过头了，但如果有机会，moment.js真的很棒!

js是一个javascript datetime库，在这种情况下使用它，你需要做:

moment(yourdate).fromNow()

http://momentjs.com/docs/#/displaying/fromnow/

2018附录:Luxon是一个新的现代图书馆，可能值得一看!

2022年附录:Day.js是一个较新的库，比Luxon轻80%左右，具有类似的功能。