PageSpeed ​​Insights

当PageSpeed Insights检测到网页上的文字太小而难以辨认时，就会触发此规则。 概览 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”，会因设备尺寸和密度而异。 点是相对于像素而定义的。一个像素是0.75点*. EM and Percentage are "relative" units: These are relative to...

当PageSpeed Insights检测到某些点按目标（例如按钮、链接或表单字段）可能过小或距离过近，以致用户不方便在触摸屏上点按时，就会触发此规则。 概览 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...

当PageSpeed Insights检测到网页内容不适合在指定尺寸的视口内水平显示，而强制用户水平移动网页以查看所有内容时，就会触发此规则。 概览 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...

当PageSpeed Insights检测到您的网页未指定视口，或者指定的视口不适合不同设备时，就会触发此规则。 概览 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...