Myer

First Contentful Paint (FCP) is a performance metric that measures the time it takes for the first piece of content to be rendered on the screen when a user navigates to a web page. This content can be any visual element on the page, such as text, images, or a background color.

FCP is important because it directly affects the perceived speed of a website, and can impact user engagement and conversion rates. A faster FCP can lead to a better user experience and improved performance.

Here are a few ways you can optimise your FCP:

1. Optimise images: Large, unoptimised images can slow down a page’s FCP. You can optimise images by compressing them, reducing their dimensions, and choosing the right format for each image.
2. Minimise HTTP requests: Each resource requested by a web page, such as images, scripts, and stylesheets, requires a separate HTTP request. Minimising the number of HTTP requests can help to reduce the time it takes for a page to render.
3. Prioritize critical content: Prioritizing critical content, such as above-the-fold content, can help to ensure that users see something on the screen quickly, even if the rest of the page is still loading.
4. Reduce server response time: A slow server response time can significantly impact FCP. Optimizing server-side code and server settings can help to reduce response times and improve FCP.
5. Use a performance monitoring tool: There are many tools available that can help you monitor your website’s performance, including FCP. These tools can help you identify performance issues and track your progress as you implement optimizations.

Largest Contentful Paint marks the time at which the largest text or image is painted. Learn more about the Largest Contentful Paint metric

Sum of all time periods between FCP and Time to Interactive, when task length exceeded 50ms, expressed in milliseconds. Learn more about the Total Blocking Time metric.

Cumulative Layout Shift measures the movement of visible elements within the viewport. Learn more about the Cumulative Layout Shift metric.

Speed Index shows how quickly the contents of a page are visibly populated. Learn more about the Speed Index metric.

Time to Interactive is the amount of time it takes for the page to become fully interactive. Learn more about the Time to Interactive metric.

The maximum potential First Input Delay that your users could experience is the duration of the longest task. Learn more about the Maximum Potential First Input Delay metric.

First Meaningful Paint measures when the primary content of a page is visible. Learn more about the First Meaningful Paint metric.

Resources are blocking the first paint of your page. Consider delivering critical JS/CSS inline and deferring all non-critical JS/styles. Learn how to eliminate render-blocking resources.

Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity. Learn how to reduce unused CSS.

Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. Learn how to reduce unused JavaScript.

Large network payloads cost users real money and are highly correlated with long load times. Learn how to reduce payload sizes.

A long cache lifetime can speed up repeat visits to your page. Learn more about efficient cache policies.

A large DOM will increase memory usage, cause longer style calculations, and produce costly layout reflows. Learn how to avoid an excessive DOM size.

Consider reducing the time spent parsing, compiling, and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to reduce Javascript execution time.

Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to minimize main-thread work

Third-party code can significantly impact load performance. Limit the number of redundant third-party providers and try to load third-party code after your page has primarily finished loading. Learn how to minimize third-party impact.

For users on slow connections, external scripts dynamically injected via document.write() can delay page load by tens of seconds. Learn how to avoid document.write().

ARIA roles enable assistive technologies to know the role of each element on the web page. If the role values are misspelled, not existing ARIA role values, or abstract roles, then the purpose of the element will not be communicated to users of assistive technologies. Learn more about ARIA roles.

Some ARIA roles have required attributes that describe the state of the element to screen readers. Learn more about roles and required attributes.

Assistive technologies, like screen readers, can't interpret ARIA attributes with invalid values. Learn more about valid values for ARIA attributes.

The value of an ARIA ID must be unique to prevent other instances from being overlooked by assistive technologies. Learn how to fix duplicate ARIA IDs.

Properly ordered headings that do not skip levels convey the semantic structure of the page, making it easier to navigate and understand when using assistive technologies. Learn more about heading order.

Visible text labels that do not match the accessible name can result in a confusing experience for screen reader users. Learn more about accessible names.

Link text (and alternate text for images, when used as links) that is discernible, unique, and focusable improves the navigation experience for screen reader users. Learn how to make links accessible.

Screen readers require list items (<li>) to be contained within a parent <ul>, <ol> or <menu> to be announced properly. Learn more about proper list structure.

Google Analytics collects data on website users and their behaviour, which can raise privacy concerns for some visitors. Website owners who use Google Analytics have access to a range of data points, including IP addresses, browser types, device information, and user behaviour on the site.

While Google Analytics does provide some tools to help website owners protect the privacy of their visitors, such as data retention controls and the ability to enable IP address anonymisation, it’s important for website owners to be transparent about the data they collect and how they use it. Website owners should also take steps to ensure that any third-party tools they use, including Google Analytics, comply with relevant privacy laws and regulations.

Additionally, some users may choose to block Google Analytics tracking using ad-blocking software or browser extensions that prevent tracking cookies from being set. This can impact the accuracy of website analytics, but website owners should respect the privacy preferences of their visitors and provide alternative means for users to access the site and its content.

The following alternatives to Google Analytics are privacy focussed, meaning they don’t compromise the visitors privacy for the sake of data collection and reporting.

• Plausible
• Cabin
• Fathom
• Simple Analytics
• Insights
• Matomo

Image natural dimensions should be proportional to the display size and the pixel ratio to maximize image clarity. Learn how to provide responsive images.

The unload event does not fire reliably and listening for it can prevent browser optimizations like the Back-Forward Cache. Use pagehide or visibilitychange events instead. Learn more about unload event listeners

Deprecated APIs will eventually be removed from the browser. Learn more about deprecated APIs.

Errors logged to the console indicate unresolved problems. They can come from network request failures and other browser concerns. Learn more about this errors in console diagnostic audit

Source maps translate minified code to the original source code. This helps developers debug in production. In addition, Lighthouse is able to provide further insights. Consider deploying source maps to take advantage of these benefits. Learn more about source maps.