Clearing all cookies with JavaScript

function deleteAllCookies() {
    var cookies = document.cookie.split(";");

    for (var i = 0; i < cookies.length; i++) {
        var cookie = cookies[i];
        var eqPos = cookie.indexOf("=");
        var name = eqPos > -1 ? cookie.substr(0, eqPos) : cookie;
        document.cookie = name + "=;expires=Thu, 01 Jan 1970 00:00:00 GMT";
    }
}

Note that this code has two limitations:

It will not delete cookies with HttpOnly flag set, as the HttpOnly flag disables Javascript's access to the cookie.

It will not delete cookies that have been set with a Path value. (This is despite the fact that those cookies will appear in document.cookie, but you can't delete it without specifying the same Path value with which it was set.)

One liner

In case you want to paste it in quickly...

document.cookie.split(";").forEach(function(c) { document.cookie = c.replace(/^ +/, "").replace(/=.*/, "=;expires=" + new Date().toUTCString() + ";path=/"); });

And the code for a bookmarklet :

javascript:(function(){document.cookie.split(";").forEach(function(c) { document.cookie = c.replace(/^ +/, "").replace(/=.*/, "=;expires=" + new Date().toUTCString() + ";path=/"); }); })();

And here's one to clear all cookies in all paths and all variants of the domain (www.mydomain.example, mydomain.example etc):

(function () {
    var cookies = document.cookie.split("; ");
    for (var c = 0; c < cookies.length; c++) {
        var d = window.location.hostname.split(".");
        while (d.length > 0) {
            var cookieBase = encodeURIComponent(cookies[c].split(";")[0].split("=")[0]) + '=; expires=Thu, 01-Jan-1970 00:00:01 GMT; domain=' + d.join('.') + ' ;path=';
            var p = location.pathname.split('/');
            document.cookie = cookieBase + '/';
            while (p.length > 0) {
                document.cookie = cookieBase + p.join('/');
                p.pop();
            };
            d.shift();
        }
    }
})();

After a bit of frustration with this myself I knocked together this function which will attempt to delete a named cookie from all paths. Just call this for each of your cookies and you should be closer to deleting every cookie then you were before.

function eraseCookieFromAllPaths(name) {
    // This function will attempt to remove a cookie from all paths.
    var pathBits = location.pathname.split('/');
    var pathCurrent = ' path=';

    // do a simple pathless delete first.
    document.cookie = name + '=; expires=Thu, 01-Jan-1970 00:00:01 GMT;';

    for (var i = 0; i < pathBits.length; i++) {
        pathCurrent += ((pathCurrent.substr(-1) != '/') ? '/' : '') + pathBits[i];
        document.cookie = name + '=; expires=Thu, 01-Jan-1970 00:00:01 GMT;' + pathCurrent + ';';
    }
}

As always different browsers have different behaviour but this worked for me. Enjoy.

If you have access to the jquery.cookie plugin, you can erase all cookies this way:

for (var it in $.cookie()) $.removeCookie(it);

As far as I know there's no way to do a blanket delete of any cookie set on the domain. You can clear a cookie if you know the name and if the script is on the same domain as the cookie.

You can set the value to empty and the expiration date to somewhere in the past:

var mydate = new Date();
mydate.setTime(mydate.getTime() - 1);
document.cookie = "username=; expires=" + mydate.toGMTString(); 

There's an excellent article here on manipulating cookies using javascript.

The following code will remove all cookies within the current domain and all trailing subdomains (www.some.sub.domain.example, .some.sub.domain.example, .sub.domain.example and so on.).

A single line vanilla JS version (I think the only one here without the use of cookie.split()):

document.cookie.replace(/(?<=^|;).+?(?=\=|;|$)/g, name => location.hostname.split('.').reverse().reduce(domain => (domain=domain.replace(/^\.?[^.]+/, ''),document.cookie=`${name}=;max-age=0;path=/;domain=${domain}`,domain), location.hostname));

This is a readable version of this single line:

document.cookie.replace(
  /(?<=^|;).+?(?=\=|;|$)/g,
  name => location.hostname
    .split(/\.(?=[^\.]+\.)/)
    .reduceRight((acc, val, i, arr) => i ? arr[i]='.'+val+acc : (arr[i]='', arr), '')
    .map(domain => document.cookie=`${name}=;max-age=0;path=/;domain=${domain}`)
);

An answer influenced by both second answer here and W3Schools

document.cookie.split(';').forEach(function(c) {
  document.cookie = c.trim().split('=')[0] + '=;' + 'expires=Thu, 01 Jan 1970 00:00:00 UTC;';
});

Seems to be working

edit: wow almost exactly the same as Zach's interesting how Stack Overflow put them next to each other.

edit: nvm that was temporary apparently

Simpler. Faster.

function deleteAllCookies() {
 var c = document.cookie.split("; ");
 for (i in c) 
  document.cookie =/^[^=]+/.exec(c[i])[0]+"=;expires=Thu, 01 Jan 1970 00:00:00 GMT";    
}

If you are concerned about clearing cookies only on a secured origin you can use the Cookie Store API and it's .delete() method.

cookieStore.getAll().then(cookies => cookies.forEach(cookie => {
    console.log('Cookie deleted:', cookie);
    cookieStore.delete(cookie.name);
}));

Visit the caniuse.com table for the Cookie Store API to check for browser support.

I don't know why the first voted answer doesn't work for me.

As this answer said:

There is no 100% solution to delete browser cookies. The problem is that cookies are uniquely identified by not just by their key "name" but also their "domain" and "path". Without knowing the "domain" and "path" of a cookie, you cannot reliably delete it. This information is not available through JavaScript's document.cookie. It's not available through the HTTP Cookie header either!

So my idea is to add a Cookie version control with the full set of setting, getting, removing of cookies:

var cookie_version_control = '---2018/5/11';

function setCookie(name,value,days) {
    var expires = "";
    if (days) {
        var date = new Date();
        date.setTime(date.getTime() + (days*24*60*60*1000));
        expires = "; expires=" + date.toUTCString();
    }
    document.cookie = name+cookie_version_control + "=" + (value || "")  + expires + "; path=/";
}

function getCookie(name) {
    var nameEQ = name+cookie_version_control + "=";
    var ca = document.cookie.split(';');
    for(var i=0;i < ca.length;i++) {
        var c = ca[i];
        while (c.charAt(0)==' ') c = c.substring(1,c.length);
        if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
    }
    return null;
}

function removeCookie(name) {   
    document.cookie = name+cookie_version_control+'=; Max-Age=-99999999;';  
}

Figured I'd share this method for clearing cookies. Perhaps it may be helpful for someone else at some point.

var cookie = document.cookie.split(';');

for (var i = 0; i < cookie.length; i++) {

    var chip = cookie[i],
        entry = chip.split("="),
        name = entry[0];

    document.cookie = name + '=; expires=Thu, 01 Jan 1970 00:00:01 GMT;';
}

I have some more sophisticated and OOP-oriented cookie control module. It also contains deleteAll method to clear all existing cookie. Make notice that this version of deleteAll method has setting path=/ that causes deleting of all cookies within current domain. If you need to delete cookies only from some scope you will have to upgrade this method my adding dynamic path parameter to this method.

There is main Cookie class:

import {Setter} from './Setter';

export class Cookie {
    /**
     * @param {string} key
     * @return {string|undefined}
     */
    static get(key) {
        key = key.replace(/([\.$?*|{}\(\)\[\]\\\/\+^])/g, '\\$1');

        const regExp = new RegExp('(?:^|; )' + key + '=([^;]*)');
        const matches = document.cookie.match(regExp);

        return matches
            ? decodeURIComponent(matches[1])
            : undefined;
    }

    /**
     * @param {string} name
     */
    static delete(name) {
        this.set(name, '', { expires: -1 });
    }

    static deleteAll() {
        const cookies = document.cookie.split('; ');

        for (let cookie of cookies) {
            const index = cookie.indexOf('=');

            const name = ~index
                ? cookie.substr(0, index)
                : cookie;

            document.cookie = name + '=;expires=Thu, 01 Jan 1970 00:00:00 GMT;path=/';
        }
    }

    /**
     * @param {string} name
     * @param {string|boolean} value
     * @param {{expires?:Date|string|number,path?:string,domain?:string,secure?:boolean}} opts
     */
    static set(name, value, opts = {}) {
        Setter.set(name, value, opts);
    }
}

Cookie setter method (Cookie.set) is rather complex so I decomposed it into other class. There is code of this one:

export class Setter {
    /**
     * @param {string} name
     * @param {string|boolean} value
     * @param {{expires?:Date|string|number,path?:string,domain?:string,secure?:boolean}} opts
     */
    static set(name, value, opts = {}) {
        value = Setter.prepareValue(value);
        opts = Setter.prepareOpts(opts);

        let updatedCookie = name + '=' + value;

        for (let i in opts) {
            if (!opts.hasOwnProperty(i)) continue;

            updatedCookie += '; ' + i;

            const value = opts[i];

            if (value !== true)
                updatedCookie += '=' + value;
        }

        document.cookie = updatedCookie;
    }

    /**
     * @param {string} value
     * @return {string}
     * @private
     */
    static prepareValue(value) {
        return encodeURIComponent(value);
    }

    /**
     * @param {{expires?:Date|string|number,path?:string,domain?:string,secure?:boolean}} opts
     * @private
     */
    static prepareOpts(opts = {}) {
        opts = Object.assign({}, opts);

        let {expires} = opts;

        if (typeof expires == 'number' && expires) {
            const date = new Date();

            date.setTime(date.getTime() + expires * 1000);

            expires = opts.expires = date;
        }

        if (expires && expires.toUTCString)
            opts.expires = expires.toUTCString();

        return opts;
    }
}

document.cookie.split(";").forEach(function(c) { 
    document.cookie = c.replace(/^ +/, "").replace(/=.*/, "=;expires=" + new Date().toUTCString() + ";path=/"); 
});
//clearing local storage
localStorage.clear();

Here's a simple code to delete all cookies in JavaScript.

function deleteAllCookies(){
   var cookies = document.cookie.split(";");
   for (var i = 0; i < cookies.length; i++)
     deleteCookie(cookies[i].split("=")[0]);
}

function setCookie(name, value, expirydays) {
 var d = new Date();
 d.setTime(d.getTime() + (expirydays*24*60*60*1000));
 var expires = "expires="+ d.toUTCString();
 document.cookie = name + "=" + value + "; " + expires;
}

function deleteCookie(name){
  setCookie(name,"",-1);
}

Run the function deleteAllCookies() to clear all cookies.

You can get a list by looking into the document.cookie variable. Clearing them all is just a matter of looping over all of them and clearing them one by one.

//Delete all cookies
function deleteAllCookies() {
    var cookies = document.cookie.split(";");
    for (var i = 0; i < cookies.length; i++) {
        var cookie = cookies[i];
        var eqPos = cookie.indexOf("=");
        var name = eqPos > -1 ? cookie.substr(0, eqPos) : cookie;
        document.cookie = name + '=;' +
            'expires=Thu, 01-Jan-1970 00:00:01 GMT;' +
            'path=' + '/;' +
            'domain=' + window.location.host + ';' +
            'secure=;';
    }
}

Functional Approach + ES6

const cookieCleaner = () => {
  return document.cookie.split(";").reduce(function (acc, cookie) {
    const eqPos = cookie.indexOf("=");
    const cleanCookie = `${cookie.substr(0, eqPos)}=;expires=Thu, 01 Jan 1970 00:00:00 GMT;`;
    return `${acc}${cleanCookie}`;
  }, "");
}

Note: Doesn't handle paths

Several answers here do not resolve the path question. I believe that: if you control the site, or part of it, you should know all the paths used. So you just have to have it delete all cookies from all paths used. Because my site already has jquery (and out of laziness) I decided to use the jquery cookie, but you can easily adapt it to pure javascript based on the other answers.

In this example I remove three specific paths that were being used by the ecommerce platform.

let mainURL = getMainURL().toLowerCase().replace('www.', '').replace('.com.br', '.com'); // i am a brazilian guy
let cookies = $.cookie();
for(key in cookies){
    // default remove
    $.removeCookie(key, {
        path:'/'
    });
    // remove without www
    $.removeCookie(key, {
        domain: mainURL,
        path: '/'
    });
    // remove with www
    $.removeCookie(key, {
        domain: 'www.' + mainURL,
        path: '/'
    });
};

// get-main-url.js v1
function getMainURL(url = window.location.href){
    url = url.replace(/.+?\/\//, ''); // remove protocol
    url = url.replace(/(\#|\?|\/)(.+)?/, ''); // remove parameters and paths
    // remove subdomain
    if( url.split('.').length === 3 ){
        url = url.split('.');
        url.shift();
        url = url.join('.');
    };
    return url;
};

I changed the .com site to .com.br because my site is multi domain and multi lingual

I'm contributing here because this function will allow you to delete all cookies (matching the path, by default no-path or \) also cookies that were set to be included on subdomains

function clearCookies( wildcardDomain=false, primaryDomain=true, path=null ){
  pathSegment = path ? '; path=' + path : ''
  expSegment = "=;expires=Thu, 01 Jan 1970 00:00:00 GMT"
  document.cookie.split(';').forEach(
    function(c) { 
      primaryDomain && (document.cookie = c.replace(/^ +/, "").replace(/=.*/, expSegment + pathSegment))
      wildcardDomain && (document.cookie = c.replace(/^ +/, "").replace(/=.*/, expSegment + pathSegment + '; domain=' + document.domain))
    }
  )
} 

After testing almost ever method listed in multiple style of browsers on multiple styles of cookies, I found almost nothing here works even 50%.

Please help correct as needed, but I'm going to throw my 2 cents in here. The following method breaks everything down and basically builds the cookie value string based on both the settings pieces as well as including a step by step build of the path string, starting with / of course.

Hope this helps others and I hope any criticism may come in the form of perfecting this method. At first I wanted a simple 1-liner as some others sought, but JS cookies are one of those things not so easily dealt with.

;(function() {
    if (!window['deleteAllCookies'] && document['cookie']) {
        window.deleteAllCookies = function(showLog) {
            var arrCookies = document.cookie.split(';'),
                arrPaths = location.pathname.replace(/^\//, '').split('/'), //  remove leading '/' and split any existing paths
                arrTemplate = [ 'expires=Thu, 01-Jan-1970 00:00:01 GMT', 'path={path}', 'domain=' + window.location.host, 'secure=' ];  //  array of cookie settings in order tested and found most useful in establishing a "delete"
            for (var i in arrCookies) {
                var strCookie = arrCookies[i];
                if (typeof strCookie == 'string' && strCookie.indexOf('=') >= 0) {
                    var strName = strCookie.split('=')[0];  //  the cookie name
                    for (var j=1;j<=arrTemplate.length;j++) {
                        if (document.cookie.indexOf(strName) < 0) break; // if this is true, then the cookie no longer exist
                        else {
                            var strValue = strName + '=; ' + arrTemplate.slice(0, j).join('; ') + ';';  //  made using the temp array of settings, putting it together piece by piece as loop rolls on
                            if (j == 1) document.cookie = strValue;
                            else {
                                for (var k=0;k<=arrPaths.length;k++) {
                                    if (document.cookie.indexOf(strName) < 0) break; // if this is true, then the cookie no longer exist
                                    else {
                                        var strPath = arrPaths.slice(0, k).join('/') + '/'; //  builds path line 
                                        strValue = strValue.replace('{path}', strPath);
                                        document.cookie = strValue;
                                    }
                                }
                            }
                        }
                    }
                }
            }
            showLog && window['console'] && console.info && console.info("\n\tCookies Have Been Deleted!\n\tdocument.cookie = \"" + document.cookie + "\"\n");
            return document.cookie;
        }
    }
})();

Jquery:

var cookies = $.cookie();
for(var cookie in cookies) {
$.removeCookie(cookie);
}

vanilla JS

function clearListCookies()
{   
 var cookies = document.cookie.split(";");
 for (var i = 0; i < cookies.length; i++)
  {   
    var spcook =  cookies[i].split("=");
    deleteCookie(spcook[0]);
  }
  function deleteCookie(cookiename)
   {
    var d = new Date();
    d.setDate(d.getDate() - 1);
    var expires = ";expires="+d;
    var name=cookiename;
    //alert(name);
    var value="";
    document.cookie = name + "=" + value + expires + "; path=/acc/html";                    
}
window.location = ""; // TO REFRESH THE PAGE
}

If you'd like to use js-cookie npm package and remove cookies by name:

import cookie from 'js-cookie'

export const removeAllCookiesByName = (cookieName: string) => {
  const hostParts = location.host.split('.')
  const domains = hostParts.reduce(
    (acc: string[], current, index) => [
      ...acc,
      hostParts.slice(index).join('.'),
    ],
    []
  )
  domains.forEach((domain) => cookie.remove(cookieName, { domain }))
}

I found a problem in IE and Edge. Webkit browsers (Chrome, safari) seem to be more forgiving. When setting cookies, always set the "path" to something, because the default will be the page that set the cookie. So if you try to expire it on a different page without specifying the "path", the path won't match and it won't expire. The document.cookie value doesn't show the path or expiration for a cookie, so you can't derive where the cookie was set by looking at the value.

If you need to expire cookies from different pages, save the path of the setting page in the cookie value so you can pull it out later or always append "; path=/;" to the cookie value. Then it will expire from any page.