Network Rail

Font files should be loaded from the same hosting as the website because

1. Increased loading time: Third-party sub-resources, such as scripts, fonts, or images, need to be downloaded from a separate server before they can be displayed on the website. This can increase the overall loading time of the page, leading to a slower user experience.
2. Dependence on external servers: The loading of third-party subresources is dependent on the availability and performance of the external servers that host them. If these servers are slow or unavailable, it can result in slow page loading times or even errors.
3. Increased risk of security threats: Third-party subresources can introduce security risks to a website, as they can contain malicious code or be used to track user activity.

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.

Serve images that are appropriately-sized to save cellular data and improve load time. Learn how to size images.

Minifying CSS files can reduce network payload sizes. Learn how to minify CSS.

Minifying JavaScript files can reduce payload sizes and script parse time. Learn how to minify JavaScript.

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.

Optimized images load faster and consume less cellular data. Learn how to efficiently encode images.

Image formats like WebP and AVIF often provide better compression than PNG or JPEG, which means faster downloads and less data consumption. Learn more about modern image formats.

Keep the server response time for the main document short because all other requests depend on it. Learn more about the Time to First Byte metric.

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.

Consider marking your touch and wheel event listeners as passive to improve your page's scroll performance. Learn more about adopting passive event listeners.

Font files should be loaded from the same hosting as the website because

1. Increased loading time: Third-party sub-resources, such as scripts, fonts, or images, need to be downloaded from a separate server before they can be displayed on the website. This can increase the overall loading time of the page, leading to a slower user experience.
2. Dependence on external servers: The loading of third-party subresources is dependent on the availability and performance of the external servers that host them. If these servers are slow or unavailable, it can result in slow page loading times or even errors.
3. Increased risk of security threats: Third-party subresources can introduce security risks to a website, as they can contain malicious code or be used to track user activity.

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.

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

Links with descriptive text can provide users with more context about the content they are clicking on, which can help them to make informed decisions about whether to follow the link or not. This is especially important for users with disabilities, as screen readers can use the link text to provide an audio description of the content.

In addition, links with descriptive text can also improve the overall user experience, as users are more likely to know what to expect when they follow a link. This can reduce the likelihood of users bouncing back from a page after finding that it’s not what they were looking for, which can help to improve the user engagement and retention on a website.

Furthermore, descriptive links can also help to improve a website\’s search engine optimisation (SEO). Search engines use the link text and surrounding context to understand the content of a page, and this information is used to determine the relevance of a page for specific search queries. Descriptive links can help search engines to understand the content of a page more accurately, which can improve its visibility and ranking in search results.

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.