當PageSpeed Insights檢測到網(wǎng)頁上的文字太小而難以辨認時，就會觸發(fā)此規(guī)則。 概覽 You can use the followingFour commonly used unitsTo specify the page font size: pixels (px), dots (pt), em (em), and percentages (%). 像素即“CSS像素”，會因設備尺寸和密度而異。 點是相對于像素而定義的。一個像素是0.75點*. EM and Percentage are "relative" units: These are relative to...

當PageSpeed Insights檢測到某些點按目標（例如按鈕、鏈接或表單字段）可能過小或距離過近，以致用戶不方便在觸摸屏上點按時，就會觸發(fā)此規(guī)則。 概覽 If the links or buttons are too small or crowded, clicking on these objects on the touch screen can be more laborious than using a traditional mouse cursor. In order to avoid the trouble of accidentally pressing the...

當PageSpeed Insights檢測到網(wǎng)頁內(nèi)容不適合在指定尺寸的視口內(nèi)水平顯示，而強制用戶水平移動網(wǎng)頁以查看所有內(nèi)容時，就會觸發(fā)此規(guī)則。 概覽 On desktop and mobile devices, users are accustomed to scrolling through websites vertically (rather than horizontally), and forcing users to scroll horizontally or zoom out to view the full web page can bring poor...

當PageSpeed Insights檢測到您的網(wǎng)頁未指定視口，或者指定的視口不適合不同設備時，就會觸發(fā)此規(guī)則。 概覽 Viewport can control how web pages are displayed on mobile devices. If no viewport is specified, the mobile device renders the Web page to the width of a typical desktop screen and adjusts the Web page to fit the screen size. By...

This rule is triggered when PageSpeed Insights detects that you are using a synchronous version of the script instead of an asynchronous version. Overview Using asynchronous scripts means that the system can render your web page more quickly, rather than forcing users to wait for the script to...

This rule is triggered when PageSpeed Insights detects that your HTML refers to a system-blocked external JavaScript file (located in the first part of the page). Overview The browser must parse the web page before it can be rendered to the user. If the browser encounters an external script...

This rule is triggered when PageSpeed Insights detects that the system needs to make more network round trips to render the first screen content of a web page. Overview If the amount of data required exceeds the limit of the initial congestion window, the system needs to make more round trips...

This rule is triggered when PageSpeed Insights detects that a Web page contains an external style sheet that prevents rendering, which delays the display of content on the screen. Overview The browser blocks the external CSS file before the screen displays the content. This causes additional...

This rule is triggered when PageSpeed Insights detects that a picture on a Web page can be optimized to reduce its size without significantly affecting its visual effect. Overview Minimize the picture size to reduce the time users wait for resources to load. Formatting and compressing pictures...

This rule is triggered when PageSpeed Insights detects that one of your resources can be reduced in size by a reduction operation. Overview Reducing resource size means removing unnecessary bytes (for example, redundant spaces, newlines, and indentation). Compressing HTML, CSS, and JavaScript...

This rule is triggered when PageSpeed Insights detects that your server response does not contain an explicit cache header or that some resources are specified to be cached only for a short period of time. Overview Browser caching of static resources can save users time if they visit your site...

This rule is triggered when PageSpeed Insights detects that your server response time exceeds 200 milliseconds. Overview Server response time represents the time needed to load the necessary HTML to start rendering the web page hosted by the server, minus the network latency between Google and...

This rule is triggered when PageSpeed Insights detects that a compressed resource on a Web page is not provided with HTTP compression. Overview Many network servers can compress files into a file by calling a third-party module or using a built-in program gzipFormat, and then send the compressed...

This rule is triggered when PageSpeed Insights detects that you used multiple redirects during the transition of the specified URL to the final destination page. Overview Because redirects trigger additional HTTP request response cycles and add additional round-trip time latency, it is critical...