Subscribe

JavaScript Remove Duplicates from Array

โœ๏ธ

Today we are learning how to remove duplicates from an array

28 Jul, 2020 ยท 2 min read

Today I want to share with you guys the easiest way to remove duplicates in an array with JavaScript.

We are going to be using the Set method for this.

BTW: I have a free Giveaway on Twitter! ๐Ÿšจ Free Giveaway

JavaScript Removing Duplicates from Array

We already had a full overview of the Set function before, but today we are using Set to remove duplicates from an array.

Let's start with the following array:

const array = ['๐ŸคŸ', '๐ŸคŸ', 1, 'abc', '๐ŸคŸ', 1];

As you can see, we have the emoji three times and the number one twice.

So make this a unique non-duplicate array we simply call Set on it.

const array = ['๐ŸคŸ', '๐ŸคŸ', 1, 'abc', '๐ŸคŸ', 1];
const set = new Set(array);
console.log(set);
// Set(3)ย {"๐ŸคŸ", 1, "abc"}

Wow, awesome and simple right!

JavaScript is not always complicated loops and functions; we have to leverage the write commands for the right solution.

Feel free to have a go on this Codepen.

See the Pen JavaScript Remove Duplicates from Array by Chris Bongers (@rebelchris) on CodePen.

Browser Support

Be aware; Set is not supported in the older IE versions!

JavaScript Set support

Thank you for reading, and let's connect!

Thank you for reading my blog. Feel free to subscribe to my email newsletter and connect on Facebook or Twitter

Spread the knowledge with fellow developers on Twitter
Tweet this tip
Powered by Webmentions - Learn more

Read next ๐Ÿ“–

JavaScript sending data between windows

9 Sep, 2022 ยท 4 min read

JavaScript sending data between windows

Using the native payment request JavaScript API

9 Aug, 2022 ยท 8 min read

Using the native payment request JavaScript API

Join <html><head><script data-ezscrex='false' data-cfasync='false' data-pagespeed-no-defer>var __ez=__ez||{};__ez.stms=Date.now();__ez.evt={};__ez.script={};__ez.ck=__ez.ck||{};__ez.template={};__ez.template.isOrig=true;__ez.queue=function(){var e=0,i=0,t=[],n=!1,s=[],r=[],o=!0,a=function(e,i,n,s,r,o,a){var l=this;this.name=e,this.funcName=i,this.parameters=null===n?null:n instanceof Array?n:[n],this.isBlock=s,this.blockedBy=r,this.deleteWhenComplete=o,this.isError=!1,this.isComplete=!1,this.isInitialized=!1,this.proceedIfError=a,this.isTimeDelay=!1,this.process=function(){u("... func = "+e),l.isInitialized=!0,l.isComplete=!0,u("... func.apply: "+e);var i=l.funcName.split("."),n=null;i.length>3||(n=3===i.length?window[i[0]][i[1]][i[2]]:2===i.length?window[i[0]][i[1]]:window[l.funcName]),null!=n&&n.apply(null,this.parameters),!0===l.deleteWhenComplete&&delete t[e],!0===l.isBlock&&(u("----- F'D: "+l.name),f())}},l=function(e,i,t,n,s,r,o){var a=this;this.name=e,this.path=i,this.async=s,this.defer=r,this.isBlock=t,this.blockedBy=n,this.isInitialized=!1,this.isError=!1,this.isComplete=!1,this.proceedIfError=o,this.isTimeDelay=!1,this.isPath=function(e){return"/"===e[0]&&"/"!==e[1]},this.getSrc=function(e){return void 0!==window.__ezScriptHost&&this.isPath(e)?window.__ezScriptHost+e:e},this.process=function(){a.isInitialized=!0,u("... file = "+e);var i=document.createElement("script");i.src=this.getSrc(this.path),!0===s?i.async=!0:!0===r&&(i.defer=!0),i.onerror=function(){u("----- ERR'D: "+a.name),a.isError=!0,!0===a.isBlock&&f()},i.onreadystatechange=i.onload=function(){var e=i.readyState;u("----- F'D: "+a.name),e&&!/loaded|complete/.test(e)||(a.isComplete=!0,!0===a.isBlock&&f())},document.getElementsByTagName("head")[0].appendChild(i)}},c=function(e,i){this.name=e,this.path="",this.async=!1,this.defer=!1,this.isBlock=!1,this.blockedBy=[],this.isInitialized=!0,this.isError=!1,this.isComplete=i,this.proceedIfError=!1,this.isTimeDelay=!1,this.process=function(){}};function d(e){!0!==h(e)&&0!=o&&e.process()}function h(e){if(!0===e.isTimeDelay&&!1===n)return u(e.name+" blocked = TIME DELAY!"),!0;if(e.blockedBy instanceof Array)for(var i=0;i<e.blockedBy.length;i++){var s=e.blockedBy[i];if(!1===t.hasOwnProperty(s))return u(e.name+" blocked = "+s),!0;if(!0===e.proceedIfError&&!0===t[s].isError)return!1;if(!1===t[s].isComplete)return u(e.name+" blocked = "+s),!0}return!1}function u(e){var i=window.location.href,t=new RegExp("[?&]ezq=([^&#]*)","i").exec(i);"1"===(t?t[1]:null)&&console.debug(e)}function f(){++e>200||(u("let's go"),m(s),m(r))}function m(e){for(var i in e)if(!1!==e.hasOwnProperty(i)){var t=e[i];!0===t.isComplete||h(t)||!0===t.isInitialized||!0===t.isError?!0===t.isError?u(t.name+": error"):!0===t.isComplete?u(t.name+": complete already"):!0===t.isInitialized&&u(t.name+": initialized already"):t.process()}}return window.addEventListener("load",(function(){setTimeout((function(){n=!0,u("TDELAY -----"),f()}),5e3)}),!1),{addFile:function(e,i,n,o,a,c,h,u){var f=new l(e,i,n,o,a,c,h);!0===u?s[e]=f:r[e]=f,t[e]=f,d(f)},addDelayFile:function(e,i){var n=new l(e,i,!1,[],!1,!1,!0);n.isTimeDelay=!0,u(e+" ... FILE! TDELAY"),r[e]=n,t[e]=n,d(n)},addFunc:function(e,n,o,l,c,h,u,f,m){!0===h&&(e=e+"_"+i++);var p=new a(e,n,o,l,c,u,f);!0===m?s[e]=p:r[e]=p,t[e]=p,d(p)},addDelayFunc:function(e,i,n){var s=new a(e,i,n,!1,[],!0,!0);s.isTimeDelay=!0,u(e+" ... FUNCTION! TDELAY"),r[e]=s,t[e]=s,d(s)},items:t,processAll:f,setallowLoad:function(e){o=e},markLoaded:function(e){if(e&&0!==e.length){if(e in t){var i=t[e];!0===i.isComplete?u(i.name+" "+e+": error loaded duplicate"):(i.isComplete=!0,i.isInitialized=!0)}else t[e]=new c(e,!0);u("markLoaded dummyfile: "+t[e].name)}},logWhatsBlocked:function(){for(var e in t)!1!==t.hasOwnProperty(e)&&h(t[e])}}}();__ez.evt.add=function(e,t,n){e.addEventListener?e.addEventListener(t,n,!1):e.attachEvent?e.attachEvent("on"+t,n):e["on"+t]=n()},__ez.evt.remove=function(e,t,n){e.removeEventListener?e.removeEventListener(t,n,!1):e.detachEvent?e.detachEvent("on"+t,n):delete e["on"+t]};__ez.script.add=function(e){var t=document.createElement("script");t.src=e,t.async=!0,t.type="text/javascript",document.getElementsByTagName("head")[0].appendChild(t)};__ez.dot={};__ez.queue.addFile('/detroitchicago/boise.js', '/detroitchicago/boise.js?gcb=195-0&cb=2', true, [], true, false, true, false);__ez.queue.addFile('/detroitchicago/memphis.js', '/detroitchicago/memphis.js?gcb=195-0&cb=21', true, [], true, false, true, false);__ez.queue.addFile('/detroitchicago/minneapolis.js', '/detroitchicago/minneapolis.js?gcb=195-0&cb=4', true, [], true, false, true, false);__ez.queue.addFile('/detroitchicago/rochester.js', '/detroitchicago/rochester.js?gcb=195-0&cb=13', false, ['/detroitchicago/memphis.js','/detroitchicago/minneapolis.js'], true, false, true, false);!function(){var e;__ez.vep=(e=[],{Add:function(i,t){__ez.dot.isDefined(i)&&__ez.dot.isValid(t)&&e.push({type:"video",video_impression_id:i,domain_id:__ez.dot.getDID(),t_epoch:__ez.dot.getEpoch(0),data:__ez.dot.dataToStr(t)})},Fire:function(){if(void 0===document.visibilityState||"prerender"!==document.visibilityState){if(__ez.dot.isDefined(e)&&e.length>0)for(;e.length>0;){var i=5;i>e.length&&(i=e.length);var t=e.splice(0,i),o=__ez.dot.getURL("/detroitchicago/grapefruit.gif")+"?orig="+(!0===__ez.template.isOrig?1:0)+"&v="+btoa(JSON.stringify(t));__ez.dot.Fire(o)}e=[]}}})}();</script><script data-ezscrex='false' data-cfasync='false' data-pagespeed-no-defer>!function(){function e(i){return e="function"==typeof Symbol&&"symbol"==typeof Symbol.iterator?function(e){return typeof e}:function(e){return e&&"function"==typeof Symbol&&e.constructor===Symbol&&e!==Symbol.prototype?"symbol":typeof e},e(i)}__ez.pel=function(){var i=[];function t(t,o,d,_,n,r,a,s){if(__ez.dot.isDefined(t)&&0!=__ez.dot.isAnyDefined(t.getSlotElementId,t.ElementId)){void 0===s&&(s=!1);var p=parseInt(__ez.dot.getTargeting(t,"ap")),f=__ez.dot.getSlotIID(t),u=__ez.dot.getAdUnit(t,s),z=parseInt(__ez.dot.getTargeting(t,"compid")),g=0,c=0,l=function(i){if("undefined"==typeof _ezim_d)return!1;var t=__ez.dot.getAdUnitPath(i).split("/").pop();if("object"===("undefined"==typeof _ezim_d?"undefined":e(_ezim_d))&&_ezim_d.hasOwnProperty(t))return _ezim_d[t];for(var o in _ezim_d)if(o.split("/").pop()===t)return _ezim_d[o];return!1}(t);"object"==e(l)&&(void 0!==l.creative_id&&(c=l.creative_id),void 0!==l.line_item_id&&(g=l.line_item_id)),__ez.dot.isDefined(f,u)&&__ez.dot.isValid(o)&&("0"===f&&!0!==s||""===u||i.push({type:"impression",impression_id:f,domain_id:__ez.dot.getDID(),unit:u,t_epoch:__ez.dot.getEpoch(0),revenue:d,est_revenue:_,ad_position:p,ad_size:"",bid_floor_filled:n,bid_floor_prev:r,stat_source_id:a,country_code:__ez.dot.getCC(),pageview_id:__ez.dot.getPageviewId(),comp_id:z,line_item_id:g,creative_id:c,data:__ez.dot.dataToStr(o),is_orig:s||__ez.template.isOrig}))}}function o(){void 0!==document.visibilityState&&"prerender"===document.visibilityState||(__ez.dot.isDefined(i)&&i.length>0&&[i.filter((function(e){return e.is_orig})),i.filter((function(e){return!e.is_orig}))].forEach((function(e){for(;e.length>0;){var i=e[0].is_orig||!1,t=5;t>e.length&&(t=e.length);var o=e.splice(0,t),d=__ez.dot.getURL("/porpoiseant/army.gif")+"?orig="+(!0===i?1:0)+"&sts="+btoa(JSON.stringify(o));(void 0!==window.isAmp&&isAmp||void 0!==window.ezWp&&ezWp)&&void 0!==window._ezaq&&_ezaq.hasOwnProperty("domain_id")&&(d+="&visit_uuid="+_ezaq.visit_uuid),__ez.dot.Fire(d)}})),i=[])}return{Add:t,AddAndFire:function(e,i){t(e,i,0,0,0,0,0),o()},AddAndFireOrig:function(e,i){t(e,i,0,0,0,0,0,!0),o()},AddById:function(e,t,o,d){var _=e.split("/");if(__ez.dot.isDefined(e)&&3===_.length&&__ez.dot.isValid(t)){var n=_[0],r={type:"impression",impression_id:_[2],domain_id:__ez.dot.getDID(),unit:n,t_epoch:__ez.dot.getEpoch(0),pageview_id:__ez.dot.getPageviewId(),data:__ez.dot.dataToStr(t),is_orig:o||__ez.template.isOrig};void 0!==d&&(r.revenue=d),i.push(r)}},Fire:o,GetPixels:function(){return i}}}()}();__ez.queue.addFile('/detroitchicago/raleigh.js', '/detroitchicago/raleigh.js?gcb=195-0&cb=6', false, [], true, false, true, false);__ez.queue.addFile('/detroitchicago/tampa.js', '/detroitchicago/tampa.js?gcb=195-0&cb=5', false, [], true, false, true, false);</script> <script data-ezscrex="false" data-cfasync="false">(function(){if("function"===typeof window.CustomEvent)return!1;window.CustomEvent=function(c,a){a=a||{bubbles:!1,cancelable:!1,detail:null};var b=document.createEvent("CustomEvent");b.initCustomEvent(c,a.bubbles,a.cancelable,a.detail);return b}})();</script><script data-ezscrex="false" data-cfasync="false">__ez.queue.addFile('/detroitchicago/tulsa.js', '/detroitchicago/tulsa.js?gcb=195-0&cb=7', false, [], true, false, true, false);</script><script type="text/javascript">var ezouid = "1";</script><base href="https://sendy.daily-dev-tips.com/api/subscribers/active-subscriber-count.php"><script type='text/javascript'> var ezoTemplate = 'old_site_noads'; if(typeof ezouid == 'undefined') { var ezouid = 'none'; } var ezoFormfactor = '1'; var ezo_elements_to_check = Array(); </script> <script data-ezscrex="false" type='text/javascript'> var soc_app_id = '0'; var did = 408517; var ezdomain = 'daily-dev-tips.com'; var ezoicSearchable = 1; </script> <script data-ezscrex="false" type="text/javascript" data-cfasync="false">var _ezaq = {"ad_cache_level":0,"ad_lazyload_version":0,"ad_load_version":0,"city":"The Dalles","country":"US","days_since_last_visit":-1,"domain_id":408517,"engaged_time_visit":0,"ezcache_level":1,"ezcache_skip_code":8,"form_factor_id":1,"framework_id":1,"is_return_visitor":false,"is_sitespeed":0,"last_page_load":"","last_pageview_id":"","lt_cache_level":0,"metro_code":820,"page_ad_positions":"","page_view_count":0,"page_view_id":"2daf0911-6958-4839-7e19-1b83275532ea","position_selection_id":0,"postal_code":"97058","pv_event_count":0,"response_size_orig":4,"response_time_orig":288,"serverid":"34.219.211.72:15785","state":"OR","t_epoch":1669521655,"template_id":120,"time_on_site_visit":0,"url":"https://sendy.daily-dev-tips.com/api/subscribers/active-subscriber-count.php","user_id":0,"word_count":1,"worst_bad_word_level":0};var _ezExtraQueries = "&ez_orig=1";</script> <script data-ezscrex='false' data-pagespeed-no-defer data-cfasync='false'> function create_ezolpl(pvID, rv) { var d = new Date(); d.setTime(d.getTime() + (365*24*60*60*1000)); var expires = "expires="+d.toUTCString(); __ez.ck.setByCat("ezux_lpl_408517=" + new Date().getTime() + "|" + pvID + "|" + rv + "; " + expires, 3); } function attach_ezolpl(pvID, rv) { if (document.readyState === "complete") { create_ezolpl(pvID, rv); } if(window.attachEvent) { window.attachEvent("onload", create_ezolpl, pvID, rv); } else { if(window.onload) { var curronload = window.onload; var newonload = function(evt) { curronload(evt); create_ezolpl(pvID, rv); }; window.onload = newonload; } else { window.onload = create_ezolpl.bind(null, pvID, rv); } } } __ez.queue.addFunc("attach_ezolpl", "attach_ezolpl", ["2daf0911-6958-4839-7e19-1b83275532ea", "false"], false, ['/detroitchicago/boise.js'], true, false, false, false); </script></head><body>1894<script type='text/javascript' style='display:none;' async> __ez.queue.addFile('/detroitchicago/edmonton.webp', '/detroitchicago/edmonton.webp?a=a&cb=0&shcb=34', true, ['/detroitchicago/minneapolis.js'], true, false, false, false); __ez.queue.addFile('/porpoiseant/jellyfish.webp', '/porpoiseant/jellyfish.webp?a=a&cb=0&shcb=34', false, [], true, false, false, false); </script> <script>__ez.queue.addFile('/tardisrocinante/vitals.js', '/tardisrocinante/vitals.js?gcb=0&cb=3', false, ['/detroitchicago/minneapolis.js'], true, false, true, false);</script> <script type="text/javascript" data-cfasync="false"></script> <script>var _audins_dom="daily_dev_tips_com",_audins_did=408517;__ez.queue.addDelayFunc("audins.js","__ez.script.add", "//go.ezoic.net/detroitchicago/audins.js?cb=195-0");</script><noscript><div style="display:none;"><img src="//pixel.quantserve.com/pixel/p-31iz6hfFutd16.gif?labels=Domain.daily_dev_tips_com,DomainId.408517" border="0" height="1" width="1" alt="Quantcast"/></div></noscript> <script>__ez.queue.addFile('/beardeddragon/drake.js', '/beardeddragon/drake.js?gcb=0&cb=4', false, [], true, false, true, false);</script></body></html> devs and subscribe to my newsletter