{"id":416864,"date":"2022-03-14T15:00:10","date_gmt":"2022-03-14T12:00:10","guid":{"rendered":"https:\/\/en.buradabiliyorum.com\/what-is-the-127-0-0-1-ip-address-and-how-do-you-use-it\/"},"modified":"2022-07-06T21:20:07","modified_gmt":"2022-07-06T18:20:07","slug":"what-is-the-127-0-0-1-ip-address-and-how-do-you-use-it","status":"publish","type":"post","link":"https:\/\/buradabiliyorum.com\/en\/what-is-the-127-0-0-1-ip-address-and-how-do-you-use-it\/","title":{"rendered":"#What Is the 127.0.0.1 IP Address, and How Do You Use It?"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_85 counter-hierarchy ez-toc-counter ez-toc-custom ez-toc-container-direction\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<label for=\"ez-toc-cssicon-toggle-item-6a3f9af85c508\" class=\"ez-toc-cssicon-toggle-label\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #dd3333;color:#dd3333\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #dd3333;color:#dd3333\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/label><input type=\"checkbox\"  id=\"ez-toc-cssicon-toggle-item-6a3f9af85c508\" checked aria-label=\"Toggle\" \/><nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-1'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/buradabiliyorum.com\/en\/what-is-the-127-0-0-1-ip-address-and-how-do-you-use-it\/#%E2%80%9CWhat_Is_the_127001_IP_Address_and_How_Do_You_Use_It%E2%80%9D\" >&#8220;What Is the 127.0.0.1 IP Address, and How Do You Use It?&#8221;<\/a><ul class='ez-toc-list-level-2' ><li class='ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/buradabiliyorum.com\/en\/what-is-the-127-0-0-1-ip-address-and-how-do-you-use-it\/#Reserved_Addresses_on_the_Internet\" >Reserved Addresses on the Internet<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/buradabiliyorum.com\/en\/what-is-the-127-0-0-1-ip-address-and-how-do-you-use-it\/#What_Is_127001\" >What Is 127.0.0.1<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/buradabiliyorum.com\/en\/what-is-the-127-0-0-1-ip-address-and-how-do-you-use-it\/#How_to_Use_127001\" >How to Use 127.0.0.1<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/buradabiliyorum.com\/en\/what-is-the-127-0-0-1-ip-address-and-how-do-you-use-it\/#What_Is_localhost\" >What Is localhost<\/a><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n<h1><span class=\"ez-toc-section\" id=\"%E2%80%9CWhat_Is_the_127001_IP_Address_and_How_Do_You_Use_It%E2%80%9D\"><\/span>&#8220;What Is the 127.0.0.1 IP Address, and How Do You Use It?&#8221;<span class=\"ez-toc-section-end\"><\/span><\/h1>\n<figure style=\"width: 1200px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium\" src=\"https:\/\/www.howtogeek.com\/wp-content\/uploads\/2021\/07\/shutterstock_606660923.png?width=1198&amp;trim=1,1&amp;bg-color=000&amp;pad=1,1\" width=\"1200\" height=\"675\"><figcaption class=\"wp-caption-text\"><a href=\"https:\/\/www.shutterstock.com\/image-vector\/abstract-world-network-internet-global-connection-606660923\" target=\"_blank\" rel=\"noopener\">TAW4\/Shutterstock.com<\/a><\/figcaption><\/figure>\n<p>127.0.0.1 is a pretty famous IP address \u2014 it\u2019s possible you\u2019ve even seen it on a t-shirt. But what exactly is it, and why is it so famous? Find out more about 127.0.0.1 here.<\/p>\n<h2 role=\"heading\" aria-level=\"2\"><span class=\"ez-toc-section\" id=\"Reserved_Addresses_on_the_Internet\"><\/span>Reserved Addresses on the Internet<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>The Internet is made up of billions of devices. They identify and communicate with each other using&nbsp;IP addresses, which are conceptually similar to phone numbers. Internet Protocol Version 4 (IPv4), which have been in use for decades, allows for nearly 4.3 billion such addresses. The successor to IPv4,&nbsp;IPv6, has more than 10^38 addresses available \u2014 enough for every grain of sand on Earth, every star in the observable universe, and every atom in every person\u2019s body to each have a unique IP address, with plenty left over.<\/p>\n<div class=\"future_hybrid_paragraph_first\"><\/div>\n<p>Despite the huge number of IP addresses now available, it is convenient to reserve some addresses, or even ranges (usually called blocks) of addresses, for specific purposes to prevent programming conflicts. Reserving addresses for specific purposes makes it easy to establish <a href=\"https:\/\/buradabiliyorum.com\/en\/category\/general\/\" data-internallinksmanager029f6b8e52c=\"3\" title=\"General\" target=\"_blank\" rel=\"noopener\">general<\/a> rules and behaviours for different IP addresses. Reserved IP addresses, like most internet standards, are established via documents called Requests for Comment, or RFCs.<\/p>\n<p>As it turns out, it is often useful to have a computer talk to itself instead of another computer. For that, you need a special reserved IP address with some unique properties \u2014 127.0.0.1.<\/p>\n<p><strong>RELATED:<\/strong>&nbsp;<strong><em>The Foundation of the Internet: TCP\/IP Turns 40<\/em><\/strong><\/p>\n<h2 role=\"heading\" aria-level=\"2\"><span class=\"ez-toc-section\" id=\"What_Is_127001\"><\/span>What Is 127.0.0.1<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>127.0.0.1 is a host loopback address. Host loopback refers to the fact that no data packet addressed to 127.0.0.1 should ever leave the computer (host), sending it \u2014 instead of being sent to the local network or the internet, it simply gets \u201clooped back\u201d on itself, and the computer sending the packet becomes the recipient.<\/p>\n<p class=\"newpage\"><a href=\"https:\/\/datatracker.ietf.org\/doc\/html\/rfc1122#page-29\" target=\"_blank\" rel=\"noopener\">RFC 1122&nbsp;<\/a>explicitly says that \u201cInternal host loopback address. Addresses of this form MUST NOT <a href=\"https:\/\/buradabiliyorum.com\/en\/category\/download-scripts-themes-apps\/\" data-internallinksmanager029f6b8e52c=\"9\" title=\"Download Scripts &amp; Themes &amp; Apps\" target=\"_blank\" rel=\"noopener\">app<\/a>ear outside a host.\u201d As a result, routers that pick up traffic directed to 127.0.0.1 are supposed to drop the packets im<a href=\"https:\/\/buradabiliyorum.com\/en\/category\/social-mediaa\/\" data-internallinksmanager029f6b8e52c=\"1\" title=\"Social Media\" target=\"_blank\" rel=\"noopener\">media<\/a>tely. This ensures that no traffic exclusively intended to be on the host computer ever makes it out onto the Internet.<\/p>\n<p>Though it is the most common and most famous, 127.0.0.1 is just one address out of a large block, 127.0.0.0 \u2013 127.255.255.255, that is reserved for loopback purposes in&nbsp;<a href=\"https:\/\/datatracker.ietf.org\/doc\/html\/rfc6890\" target=\"_blank\" rel=\"noopener\">RFC 6890<\/a><a href=\"https:\/\/datatracker.ietf.org\/doc\/html\/rfc5735\">.<\/a><\/p>\n<div class=\"future_hybrid_paragraph\"><\/div>\n<p>IPv6 has a loopback address, too. Fully written out it is 0000:0000:0000:0000:0000:0000:0000:0001, though that is usually truncated to ::1 for convenience.<\/p>\n<h2 role=\"heading\" aria-level=\"2\"><span class=\"ez-toc-section\" id=\"How_to_Use_127001\"><\/span>How to Use 127.0.0.1<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>So why would you want packets to loop back to the same computer? There are a few common use cases.<\/p>\n<p>The first is testing purposes \u2014 if you have a&nbsp;server or website you eventually intend to host&nbsp;over a LAN or on the Internet, you can run the server and client on the same computer to make sure all the fundamentals are working correctly first. For example, if you were&nbsp;hosting a dedicated Minecraft server&nbsp;on your local machine, you would connect to it by entering 127.0.0.1 as the IP address. The same would apply to almost any locally hosted server. Removing complications related to networking, like port configuration and latency issues for example, can make the troubleshooting process more efficient.<\/p>\n<p>It is also possible you just want to run a service that is&nbsp;<em>only&nbsp;<\/em>accessible to you, on your local device. This is relatively common in the self-hosting community \u2014 it doesn\u2019t make sense to unnecessarily expose a service to outside devices and threats.<\/p>\n<p>The hosts file can be used to specify what IP address corresponds to a given domain name. Functionally, this lets you use 127.0.0.1 in your&nbsp;hosts file to block web traffic. For example, if you were to tell your computer to look for facebook.com at 127.0.0.1, it would fail to connect, effectively blocking it unless you had facebook.com\u2019s actual IP memorized.<\/p>\n<h2 role=\"heading\" aria-level=\"2\"><span class=\"ez-toc-section\" id=\"What_Is_localhost\"><\/span>What Is localhost<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>In most cases, localhost is just shorthand that refers to 127.0.0.1 by default. It can be changed though \u2014 if you edit your hosts file, you can make localhost refer to any of the 127.X.X.X reserved addresses. You can also create other localhosts, like localhost2, that can refer to 127.0.0.2, for example.<\/p>\n<p>As IPv6 is adopted more rapidly, it is likely that more and more devices will use ::1 for the default loopback address. However, 127.0.0.1 has been in use for decades, and will remain in use for the foreseeable future.<\/p>\n<p><strong>Related article :&nbsp;<a href=\"https:\/\/www.beenverified.com\/crime\/what-can-people-do-with-your-ip-address\/\" target=\"_blank\" rel=\"noopener\">What Can Someone Do With Your IP Address?<\/a><\/strong><\/p>\n<div><!-- UNCACHED CONTENT --><\/div>\n<blockquote><p><strong><span style=\"color: #ff6600;\">If you liked the article, do not forget to share it with your friends. Follow us on&nbsp;<span style=\"color: #ff0000;\"><a style=\"color: #ff0000;\" href=\"https:\/\/news.google.com\/publications\/CAAqBwgKMLG0nwswvr63Aw\" target=\"_blank\" rel=\"nofollow noopener noreferrer\">Google News<\/a><\/span>&nbsp;too, click on the star and choose us from your favorites.<\/span><\/strong><\/p><\/blockquote>\n<blockquote>\n<p style=\"text-align: center;\">For forums sites go to <span style=\"color: #ff9900;\"><a style=\"color: #ff9900;\" href=\"https:\/\/forum.buradabiliyorum.com\/\" target=\"_blank\" rel=\"noopener\">Forum.BuradaBiliyorum.Com<\/a><\/span><\/p>\n<\/blockquote>\n<blockquote>\n<p style=\"text-align: center;\"><strong>If you want to read more like this article, you can visit our <span style=\"color: #ff9900;\"><a style=\"color: #ff9900;\" href=\"https:\/\/en.buradabiliyorum.com\/technology\/\" target=\"_blank\" rel=\"noopener\">Technology category.<\/a><\/span><\/strong><\/p>\n<\/blockquote>\n<p><span style=\"color: black;\"><a style=\"color: #ff9900;\" href=\"https:\/\/www.howtogeek.com\/789017\/what-is-the-127.0.0.1-ip-address-and-how-do-you-use-it\/\" target=\"_blank\" rel=\"noopener\">Source<\/a><\/span><\/p>\n","protected":false},"excerpt":{"rendered":"<p>&#8220;What Is the 127.0.0.1 IP Address, and How Do You Use It?&#8221; 127.0.0.1 is a pretty famous IP address \u2014 it\u2019s possible you\u2019ve even seen it on a t-shirt. But what exactly is it, and why is it so famous? Find out more about 127.0.0.1 here. Reserved Addresses on the Internet The Internet is made&#8230;<\/p>\n","protected":false},"author":1,"featured_media":416865,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"fifu_image_url":"https:\/\/www.howtogeek.com\/wp-content\/uploads\/2021\/07\/shutterstock_606660923.png?height=200p&trim=2,2,2,2","fifu_image_alt":"#What Is the 127.0.0.1 IP Address, and How Do You Use It?","footnotes":""},"categories":[18],"tags":[],"class_list":["post-416864","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-technology"],"_links":{"self":[{"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/posts\/416864","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/comments?post=416864"}],"version-history":[{"count":0,"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/posts\/416864\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/media\/416865"}],"wp:attachment":[{"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/media?parent=416864"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/categories?post=416864"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/tags?post=416864"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}