{"id":17643,"date":"2021-11-15T12:58:48","date_gmt":"2021-11-15T18:58:48","guid":{"rendered":"https:\/\/www.dotcom-tools.com\/web-performance\/?page_id=17643"},"modified":"2021-11-15T12:58:48","modified_gmt":"2021-11-15T18:58:48","slug":"reduce-unused-javascript","status":"publish","type":"page","link":"https:\/\/www.dotcom-tools.com\/web-performance\/lighthouse\/reduce-unused-javascript\/","title":{"rendered":"Lighthouse Optimizations &#8211; Reduce Unused JavaScript"},"content":{"rendered":"<p>[vc_row full_width=&#8221;stretch_row&#8221; gap=&#8221;25&#8243; equal_height=&#8221;yes&#8221; content_placement=&#8221;middle&#8221; css=&#8221;.vc_custom_1636408663624{padding-top: 100px !important;padding-bottom: 100px !important;background-image: url(https:\/\/www.dotcom-tools.com\/blog\/wp-content\/uploads\/2015\/09\/hero-section-with-description-3320.jpg?id=15799) !important;background-position: center !important;background-repeat: no-repeat !important;background-size: cover !important;}&#8221;][vc_column css=&#8221;.vc_custom_1636409653940{padding-top: 30px !important;padding-bottom: 30px !important;background-color: #e6eaef !important;}&#8221;][vc_custom_heading text=&#8221;<b>Reduce Unused JavaScript<\/b>&#8221; font_container=&#8221;tag:h1|font_size:40|text_align:center|color:%232b2b2b|line_height:1.5&#8243; use_theme_fonts=&#8221;yes&#8221; css=&#8221;.vc_custom_1637002652680{padding-top: 30px !important;padding-bottom: 30px !important;}&#8221;][\/vc_column][\/vc_row][vc_row margin_top=&#8221;40&#8243; margin_bottom=&#8221;30px&#8221; css=&#8221;.vc_custom_1636409410012{margin-bottom: 30px !important;}&#8221;][vc_column][vc_custom_heading text=&#8221;JavaScript: A Major Factor to Web Page Performance&#8221; font_container=&#8221;tag:h2|font_size:35|text_align:center|color:%232b2b2b|line_height:1.5&#8243; use_theme_fonts=&#8221;yes&#8221;][vc_column_text]<\/p>\n<p style=\"font-size: 16px;\">Like CSS, JavaScript is a render-blocking resource that needs to be optimized appropriately so that it does not delay other elements. If you have any JavaScript that is no longer being used, but is still in your code, the browser still must waste resources having to download, render, and execute this code. And that is all before being able to move on to the next piece of work. And even if any non-critical or unused JavaScript is lazy loaded and not needed for any above-the-fold content, it will still take browser bandwidth from other tasks to process. Lighthouse will flag any JavaScript file that is discovered to have more than 20KiB of unused JavaScript code. <\/p>\n<p>[\/vc_column_text][vc_custom_heading text=&#8221;Benefits of Reducing Unused JavaScript&#8221; font_container=&#8221;tag:h3|font_size:30|text_align:center|color:%232b2b2b|line_height:1.5&#8243; use_theme_fonts=&#8221;yes&#8221;][vc_column_text]<\/p>\n<p style=\"font-size: 16px;\">Naturally, the more JavaScript code you have on your page, the longer it is going to take the browser to download, render, and execute. And that goes for JavaScript that is not even being used. If it is on the page, the browser is going to have to spend time and resources processing it. This makes it even more important to regularly review and optimize your code where possible.  <\/p>\n<p style=\"font-size: 16px;\">Like we have mentioned before, optimizing code benefits your mobile users as well. You can reduce the reliance on the browser to process JavaScript and help reduce bandwidth that is required. You want to be able to separate your critical JavaScript from non-critical JavaScript so that it does not delay the page load process any more than it must. There are several ways to remove unused JavaScript. Frameworks like Angular provide tools to identify unused JavaScript. CMS tools like WordPress also provide plugins, which are great for building interactive elements within your page but can also add a lot of JavaScript. Review your plugins to ensure they do not contain any unused JavaScript that could be slowing down page load times. <\/p>\n<p>[\/vc_column_text][\/vc_column][\/vc_row][vc_row margin_top=&#8221;60&#8243; margin_bottom=&#8221;0&#8243; css=&#8221;.vc_custom_1636595147911{margin-bottom: 15px !important;}&#8221;][vc_column width=&#8221;1\/3&#8243; css=&#8221;.vc_custom_1636595227743{padding-top: 60px !important;padding-bottom: 60px !important;padding-left: 10px !important;background-color: #f6f6f6 !important;}&#8221;][vc_single_image image=&#8221;17233&#8243; alignment=&#8221;center&#8221; style=&#8221;vc_box_rounded&#8221;][vc_custom_heading text=&#8221;<b>Lighthouse<\/b>&#8221; font_container=&#8221;tag:p|font_size:20|text_align:center|color:%232b2b2b|line_height:1&#8243; use_theme_fonts=&#8221;yes&#8221;][vc_column_text]<\/p>\n<p style=\"text-align: center;\">Lighthouse is an open-source tool that is used to run an audit against your web pages and provides scores and suggestions for improving page performance, accessibility, SEO, and more.<\/p>\n<p>[\/vc_column_text][vc_btn title=&#8221;Learn More&#8221; style=&#8221;flat&#8221; color=&#8221;primary&#8221; align=&#8221;center&#8221; i_icon_fontawesome=&#8221;fas fa-location-arrow&#8221; add_icon=&#8221;true&#8221; link=&#8221;url:https%3A%2F%2Fwww.dotcom-tools.com%2Fweb-performance%2Flighthouse%2F&#8221;][\/vc_column][vc_column width=&#8221;1\/3&#8243; css=&#8221;.vc_custom_1636595173585{padding-top: 60px !important;padding-bottom: 60px !important;background-color: #f6f6f6 !important;}&#8221;][vc_single_image image=&#8221;17284&#8243; alignment=&#8221;center&#8221; style=&#8221;vc_box_rounded&#8221;][vc_custom_heading text=&#8221;<b>PageSpeed Terms<\/b>&#8221; font_container=&#8221;tag:p|font_size:20|text_align:center|color:%232b2b2b|line_height:1&#8243; use_theme_fonts=&#8221;yes&#8221;][vc_column_text]<\/p>\n<p style=\"text-align: center;\">PageSpeed Insights is a tool created by Google that reports on the performance of a page on both mobile and desktop devices, and provides suggestions on how that page may be improved.<\/p>\n<p>[\/vc_column_text][vc_btn title=&#8221;Learn More&#8221; style=&#8221;flat&#8221; color=&#8221;primary&#8221; align=&#8221;center&#8221; i_icon_fontawesome=&#8221;fas fa-location-arrow&#8221; add_icon=&#8221;true&#8221; link=&#8221;url:https%3A%2F%2Fwww.dotcom-tools.com%2Fweb-performance%2Fpagespeed%2F&#8221;][\/vc_column][vc_column width=&#8221;1\/3&#8243; css=&#8221;.vc_custom_1636595196399{padding-top: 60px !important;padding-right: 10px !important;padding-bottom: 60px !important;background-color: #f6f6f6 !important;}&#8221;][vc_single_image image=&#8221;17281&#8243; alignment=&#8221;center&#8221; style=&#8221;vc_box_rounded&#8221;][vc_custom_heading text=&#8221;<b>YSlow<\/b>&#8221; font_container=&#8221;tag:p|font_size:20|text_align:center|color:%232b2b2b|line_height:1&#8243; use_theme_fonts=&#8221;yes&#8221;][vc_column_text]<\/p>\n<p style=\"text-align: center;\">YSlow is an open-source website analysis tool that can be used to identify web page performance issues. Learn more about the YSlow to enhance your web pages and the user experience.<\/p>\n<p>[\/vc_column_text][vc_btn title=&#8221;Learn More&#8221; style=&#8221;flat&#8221; color=&#8221;primary&#8221; align=&#8221;center&#8221; i_icon_fontawesome=&#8221;fas fa-location-arrow&#8221; add_icon=&#8221;true&#8221; link=&#8221;url:https%3A%2F%2Fwww.dotcom-tools.com%2Fweb-performance%2Fyslow%2F&#8221;][\/vc_column][\/vc_row]<\/p>\n","protected":false},"excerpt":{"rendered":"<p>[vc_row full_width=&#8221;stretch_row&#8221; gap=&#8221;25&#8243; equal_height=&#8221;yes&#8221; content_placement=&#8221;middle&#8221; css=&#8221;.vc_custom_1636408663624{padding-top: 100px !important;padding-bottom: 100px !important;background-image: url(https:\/\/www.dotcom-tools.com\/blog\/wp-content\/uploads\/2015\/09\/hero-section-with-description-3320.jpg?id=15799) !important;background-position: center !important;background-repeat: no-repeat !important;background-size: cover !important;}&#8221;][vc_column css=&#8221;.vc_custom_1636409653940{padding-top: 30px !important;padding-bottom: 30px !important;background-color: #e6eaef !important;}&#8221;][vc_custom_heading text=&#8221;Reduce Unused JavaScript&#8221; font_container=&#8221;tag:h1|font_size:40|text_align:center|color:%232b2b2b|line_height:1.5&#8243; use_theme_fonts=&#8221;yes&#8221; css=&#8221;.vc_custom_1637002652680{padding-top: 30px !important;padding-bottom: 30px !important;}&#8221;][\/vc_column][\/vc_row][vc_row margin_top=&#8221;40&#8243; margin_bottom=&#8221;30px&#8221; css=&#8221;.vc_custom_1636409410012{margin-bottom: 30px !important;}&#8221;][vc_column][vc_custom_heading text=&#8221;JavaScript: A Major Factor to Web Page Performance&#8221; font_container=&#8221;tag:h2|font_size:35|text_align:center|color:%232b2b2b|line_height:1.5&#8243; use_theme_fonts=&#8221;yes&#8221;][vc_column_text] Like CSS, JavaScript is a&hellip;<\/p>\n","protected":false},"author":7,"featured_media":0,"parent":17260,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v17.6 (Yoast SEO v19.1) - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\r\n<title>Lighthouse Optimizations - Reduce Unused JavaScript | Dotcom-Monitor Tools Blog<\/title>\r\n<meta name=\"description\" content=\"Looking to reduce unused JavaScript? Did you get a Lighthouse recommendation? Learn more about this optimization and how Dotcom-Tools can help!\" \/>\r\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\r\n<link rel=\"canonical\" href=\"https:\/\/www.dotcom-tools.com\/web-performance\/lighthouse\/reduce-unused-javascript\/\" \/>\r\n<meta property=\"og:locale\" content=\"en_US\" \/>\r\n<meta property=\"og:type\" content=\"article\" \/>\r\n<meta property=\"og:title\" content=\"Lighthouse Optimizations - Reduce Unused JavaScript\" \/>\r\n<meta property=\"og:description\" content=\"Looking to reduce unused JavaScript? Did you get a Lighthouse recommendation? Learn more about this optimization and how Dotcom-Tools can help!\" \/>\r\n<meta property=\"og:url\" content=\"https:\/\/www.dotcom-tools.com\/web-performance\/lighthouse\/reduce-unused-javascript\/\" \/>\r\n<meta property=\"og:site_name\" content=\"Dotcom-Monitor Tools Blog\" \/>\r\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/dotcommonitor\" \/>\r\n<meta name=\"twitter:card\" content=\"summary\" \/>\r\n<meta name=\"twitter:site\" content=\"@dotcom_monitor\" \/>\r\n<meta name=\"twitter:label1\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"4 minutes\" \/>\r\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebSite\",\"@id\":\"https:\/\/www.dotcom-tools.com\/web-performance\/#website\",\"url\":\"https:\/\/www.dotcom-tools.com\/web-performance\/\",\"name\":\"Dotcom-Monitor Tools Blog\",\"description\":\"Let&#039;s Make the Web a Faster Place.\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/www.dotcom-tools.com\/web-performance\/?s={search_term_string}\"},\"query-input\":\"required name=search_term_string\"}],\"inLanguage\":\"en-US\"},{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.dotcom-tools.com\/web-performance\/lighthouse\/reduce-unused-javascript\/#webpage\",\"url\":\"https:\/\/www.dotcom-tools.com\/web-performance\/lighthouse\/reduce-unused-javascript\/\",\"name\":\"Lighthouse Optimizations - Reduce Unused JavaScript | Dotcom-Monitor Tools Blog\",\"isPartOf\":{\"@id\":\"https:\/\/www.dotcom-tools.com\/web-performance\/#website\"},\"datePublished\":\"2021-11-15T18:58:48+00:00\",\"dateModified\":\"2021-11-15T18:58:48+00:00\",\"description\":\"Looking to reduce unused JavaScript? Did you get a Lighthouse recommendation? Learn more about this optimization and how Dotcom-Tools can help!\",\"breadcrumb\":{\"@id\":\"https:\/\/www.dotcom-tools.com\/web-performance\/lighthouse\/reduce-unused-javascript\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/www.dotcom-tools.com\/web-performance\/lighthouse\/reduce-unused-javascript\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/www.dotcom-tools.com\/web-performance\/lighthouse\/reduce-unused-javascript\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/www.dotcom-tools.com\/web-performance\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Lighthouse Optimizations\",\"item\":\"https:\/\/www.dotcom-tools.com\/web-performance\/lighthouse\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Lighthouse Optimizations &#8211; Reduce Unused JavaScript\"}]}]}<\/script>\r\n<!-- \/ Yoast SEO Premium plugin. -->","yoast_head_json":{"title":"Lighthouse Optimizations - Reduce Unused JavaScript | Dotcom-Monitor Tools Blog","description":"Looking to reduce unused JavaScript? Did you get a Lighthouse recommendation? Learn more about this optimization and how Dotcom-Tools can help!","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.dotcom-tools.com\/web-performance\/lighthouse\/reduce-unused-javascript\/","og_locale":"en_US","og_type":"article","og_title":"Lighthouse Optimizations - Reduce Unused JavaScript","og_description":"Looking to reduce unused JavaScript? Did you get a Lighthouse recommendation? Learn more about this optimization and how Dotcom-Tools can help!","og_url":"https:\/\/www.dotcom-tools.com\/web-performance\/lighthouse\/reduce-unused-javascript\/","og_site_name":"Dotcom-Monitor Tools Blog","article_publisher":"https:\/\/www.facebook.com\/dotcommonitor","twitter_card":"summary","twitter_site":"@dotcom_monitor","twitter_misc":{"Est. reading time":"4 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebSite","@id":"https:\/\/www.dotcom-tools.com\/web-performance\/#website","url":"https:\/\/www.dotcom-tools.com\/web-performance\/","name":"Dotcom-Monitor Tools Blog","description":"Let&#039;s Make the Web a Faster Place.","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.dotcom-tools.com\/web-performance\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"en-US"},{"@type":"WebPage","@id":"https:\/\/www.dotcom-tools.com\/web-performance\/lighthouse\/reduce-unused-javascript\/#webpage","url":"https:\/\/www.dotcom-tools.com\/web-performance\/lighthouse\/reduce-unused-javascript\/","name":"Lighthouse Optimizations - Reduce Unused JavaScript | Dotcom-Monitor Tools Blog","isPartOf":{"@id":"https:\/\/www.dotcom-tools.com\/web-performance\/#website"},"datePublished":"2021-11-15T18:58:48+00:00","dateModified":"2021-11-15T18:58:48+00:00","description":"Looking to reduce unused JavaScript? Did you get a Lighthouse recommendation? Learn more about this optimization and how Dotcom-Tools can help!","breadcrumb":{"@id":"https:\/\/www.dotcom-tools.com\/web-performance\/lighthouse\/reduce-unused-javascript\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.dotcom-tools.com\/web-performance\/lighthouse\/reduce-unused-javascript\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/www.dotcom-tools.com\/web-performance\/lighthouse\/reduce-unused-javascript\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.dotcom-tools.com\/web-performance\/"},{"@type":"ListItem","position":2,"name":"Lighthouse Optimizations","item":"https:\/\/www.dotcom-tools.com\/web-performance\/lighthouse\/"},{"@type":"ListItem","position":3,"name":"Lighthouse Optimizations &#8211; Reduce Unused JavaScript"}]}]}},"_links":{"self":[{"href":"https:\/\/www.dotcom-tools.com\/web-performance\/wp-json\/wp\/v2\/pages\/17643"}],"collection":[{"href":"https:\/\/www.dotcom-tools.com\/web-performance\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.dotcom-tools.com\/web-performance\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.dotcom-tools.com\/web-performance\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/www.dotcom-tools.com\/web-performance\/wp-json\/wp\/v2\/comments?post=17643"}],"version-history":[{"count":2,"href":"https:\/\/www.dotcom-tools.com\/web-performance\/wp-json\/wp\/v2\/pages\/17643\/revisions"}],"predecessor-version":[{"id":17645,"href":"https:\/\/www.dotcom-tools.com\/web-performance\/wp-json\/wp\/v2\/pages\/17643\/revisions\/17645"}],"up":[{"embeddable":true,"href":"https:\/\/www.dotcom-tools.com\/web-performance\/wp-json\/wp\/v2\/pages\/17260"}],"wp:attachment":[{"href":"https:\/\/www.dotcom-tools.com\/web-performance\/wp-json\/wp\/v2\/media?parent=17643"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}