How To Optimize Website Speed
Running a speed test is the first part of your website optimization journey.
Once you have your metrics, you need to know how to interpret them and what to do to fix them.
In the Metrics Overview area of your website speed report, you’ll see the key metrics we’ll focus on to help speed up your site:
In addition, you can use the query waterfall to see how long the query takes and how it impacts the metric.
How To Speed Up First Contentful Paint (FCP)
Let’s start by making your website appear sooner for your visitors; we will tackle First Contentful Paint, first.
What Is First Contentful Paint?
First Contentful Paint measures how long it takes for the content of the page to appear after the visitor to the page.
It is important that your key content appears quickly to keep your visitors from leaving your website. The faster users leave your website, the faster Google learns that the page experience may be bad.
But how do you know what is causing your website to be slow?
How do you find out which server problem is slowing down your website? Let’s find out.
Why Is My First Contentful Paint Taking So Long?
Your FCP can be affected by server connection speed, server requests, resource constraints, and more.
It sounds like a lot, but there’s an easy way to see what’s slowing down your FCP – the request waterfall.
This useful tool shows what requests your website is making and when each request starts and ends.
For example, in this screenshot, we first see a request for an HTML document and then two requests to open the stylesheets referenced in that document.
Screenshot showing debug data for Cat Contentful First metrics at DebugBear, October 2022
Does the First Contentful paint happen after 0.6 seconds? We can break down what is happening on the page to understand this.
Understanding What Happens Before A First Contentful Paint
Before the first piece of content can be loaded on your web page, your user’s browser must first connect to your server and retrieve the content.
If this process takes a long time, then it will take a long time for your users to view your website.
Your goal is to learn what’s happening before your website even starts to load so you can point out problems and speed up the experience.
Page Load Part 1: Browser Establishes Server Connection
Before requesting a website from a server, your browser must establish a network connection to that server.
This usually takes three steps:
These three steps are performed by the browser, one after the other. Each step requires a round trip from your visitor’s browser to your website’s server.
In this case, it takes around 251 milliseconds to establish a server connection.
A DebugBear screenshot showing the network journey used to establish a server connection, October 2022
Page Load Part 2: The Browser Requests an HTML Document (Time for the First Byte to Happen Here)
Once the server connection is established, your visitors’ browser can request the HTML code that contains the content of your website. This is called an HTTP request.
In this case, the HTTP request takes 102 milliseconds. This duration includes both the time spent in the round trip network and the time spent waiting for the server to produce a response.
After 251 milliseconds to make the connection and 102 milliseconds to make the HTTP request, your visitor’s browser can finally start downloading the HTML response.
This milestone is called Time to First Byte (TTFB). In this case, it happened after a total of 353 milliseconds.
After the server response is ready, your visitor’s browser spends extra time downloading the HTML code. In this case, the response is quite small and the download takes only 10 milliseconds extra.
DebugBear screenshot showing the different components of an HTTP request, October 2022
Page Load Part 3: Your Website Loads Additional Render-Blocking Resources
The browser does not render, or display, the page immediately after loading the document. Instead, there are usually additional sources that get in the way.
Most pages will look bad without visual styling, so CSS stylesheets are loaded before a page starts rendering.
Loading 2 additional style sheets in this website speed test example took 137 milliseconds.
Note that this request does not require a new server connection. CSS files are loaded from the same domain as before and can reuse existing connections.
DebugBear screenshot showing additional blocking resources loaded after HTML document, October 2022
Page Loads Part 4: Browser Rendering Pages
Finally, after all the necessary resources have been loaded, your visitor’s browser can start rendering the page. However, doing this work also takes some processing time – in this case, 66 milliseconds. This is indicated by an orange CPU task marker in the waterfall view.
DebugBear screenshot showing the steps from loading an HTML document to rendering a web page, October 2022
We now understand why FCP occurs after 632 milliseconds:
Other processing tasks include small jobs such as running inline scripts or parsing HTML and CSS code after download. You can see this activity as a small gray line just below the Rendering filmstrip.
How To Optimize First Contentful Paint (FCP)
Now that you understand what drives your website to work, you can think about how to optimize it.
Now that the initial pieces of your website load faster, it’s time to focus on making the full site load faster.
How Speed Up Largest Contentful Paint (LCP) With DebugBear’s Recommendations
There are many ways to speed up your LCP.
To make it easier, DebugBear gives us some great steps in its Recommendations section.
Let’s see some examples of recommendations and learn how to speed up the LCP of this website.
Recommendation 1: Initiate LCP Image Requests From The HTML Document
If the largest content element on your page is an image, it is a good practice to ensure that the URL is directly contained in the initial HTML document. This will help it start loading as soon as possible.
However, this best practice is not always used, and sometimes it takes a long time before the browser discovers that it needs to download the main image.
In the example below, the largest content, which is an image, is added to the page using JavaScript. As a result, the browser must download and run a 200-kilobyte script before it finds the image and starts downloading it.
A DebugBear screenshot showing the chain of sequential requests leading up to the image request, October 2022
How to Fix: Depending on the website there are two possible solutions.
Solution 1: If you use JavaScript to load large images, then optimize the image size and remove the lazy loading script or replace it with a modern loading = “lazy” attribute, which does not require JavaScript.
Solution 2: In other cases, server-side rendering will avoid having to download a JavaScript application before the page can be rendered. However, this can sometimes be complicated to implement.
Recommendation 2: Ensure LCP Images Are Loaded With High Priority
After loading the page’s HTML code, your browser may find that, in addition to your main image, a large number of additional resources such as stylesheets may need to be loaded.
The goal here is to make sure your main image is large enough to meet Google’s Largest Fill Color requirement.
Other resources, such as third-party analytics scripts, are not as important as your main image.
Additionally, most images referenced in your site’s HTML will be below the fold after the page has been rendered. Some can be hidden completely in the nested header navigation.
Because of this, browsers initially set the priority of all image requests to Low. After the page has been created, the browser finds out which images are important and changes their priority. You can see an example of that on the screen below, as indicated by the asterisk in the priority column.
DebugBear screenshot shows LCP image loaded with low initial priority, October 2022
The waterfall shows that when the browser finds out about the image early on, it doesn’t start downloading it, as indicated by the gray bar.
How to Fix: To solve this you can use a new browser feature called priority instructions. If you add the fetchpriority=”high” attribute to the img element, the browser will start loading the image right from the beginning.
Recommendation 3: Don’t Hide Page Content Using CSS
Sometimes you can see the request waterfall and all the blocking resources are loaded but still, no page content appears. What’s up?
A/B testing tools often hide page content until test variations have been applied to content elements on the page. In that case, the browser has rendered the page but all the content is transparent.
What can you do if you can’t remove the A/B testing tool?
How to Fix: Check if you can configure the tool to only hide content affected by A/B testing. Alternatively, you can check if there is a way to make the A/B testing tool faster.
DebugBear screenshot showing a rendering of a filmstrip where content is hidden by the A/B testing tool, October 2022
Monitor Your Site Speed With DebugBear
Want to keep testing your website? Try our paid monitoring tool with a free 14-day trial.
That way, you can check whether your performance optimization is working and be alert to performance regressions on your site.
Screenshot showing site speed trends for websites at DebugBear, October 2022
The opinions expressed in this article are those of the sponsor themselves.
Another way to check if a website is down is to use the Ping command line program. Open your command line in Windows (here’s how it works in Windows 7 and 8.1), and type ping www.facebook.com or whatever the name of the site you’re checking out. Make sure you include www otherwise it won’t work.
What is performance testing in QA?
Performance testing is a test measure that evaluates the speed, responsiveness and stability of a computer, network, software program or device under workload. Organizations will run performance tests to identify performance-related bottlenecks.
What is meant by performance testing? What is performance testing? Performance testing is the practice of evaluating how a system performs in terms of responsiveness and stability under a specific workload. Performance tests are usually executed to test the speed, robustness, reliability, and size of the application.
What do we do in performance testing?
Performance testing determines whether the high speed, scalability, and stability of the system is achieved by the system under high demand.
What comes under performance testing?
Demystifying the Six Major Types of Test Performance
- Stress Test. This test pushes the application beyond normal load conditions to determine which components fail first. …
- Spike test. …
- Load test. …
- Durability Test. …
- Test Volume. …
- Scalability Test.
What type of QA is performance testing?
Performance Testing is performed to assess the performance of a particular system component under a specific workload. During this test, system components are monitored to verify the stability of the system under test. Performance Testing is a type of Non-Functional Testing.
What type of testing is performance testing?
Performance testing is a non-functional software testing technique that determines how well the stability, speed, scalability, and responsiveness of an application holds up under a given workload.
Is performance testing Part of QA?
As an integral part of QA, testing determines product quality and helps improve it in the long term. Neglecting load and performance testing activities can cause downtime.
Is performance testing is manual or automation?
| Test the performance | Functional Testing | |
|---|---|---|
| Test Approach | Automation preferred | Manual or Automatic or Crowdsource |
| Emulate a production test environment | Liked it | It is not mandatory |
| Infrastructure Requirements | high | Minimum |
| Time taken to test | Less | More |
What is performance testing and types?
Performance testing is a form of software testing that focuses on how the system performs under a certain load. This is not about finding bugs or software defects. Different types of performance tests measure based on benchmarks and standards.
Is JMeter free tool?
Open-source – JMeter is open source software. This means that it can be downloaded for free. It is also a 100% pure Java application. Developers can use the source code, can modify and customize it according to their requirements.
Is JMeter open-source? The Apache JMeter⢠application is an open source software, 100% pure Java application designed to test functional behavior and measure performance. It was originally designed for testing Web Applications but has since expanded to other testing functions.
Is JMeter paid?
Apache JMeter is a free and open-source system for performance testing. It allows you to simulate the workload and users of your web application to test how your application performs when used by real users.
What license comes under JMeter?
| Screenshot of Apache JMeter 5.0 with HTTP(S) Test Script Recorder element | |
|---|---|
| Written in | Java |
| type | Load test |
| license | Apache License 2.0 |
| Website | jmeter.apache.org |
Is JMeter completely free?
It’s free, very intuitive and has all the possibilities you need to automate your work. Another big advantage of JMeter: open source. You can download the source and make modifications if you like.
Which is better postman or JMeter?
I find JMeter fit better for complexity, powerful scripting, CICD templates, simple end-points, total load, and performance testing, thus re-use test. Remember, both devices can perform all the above operations.
Is JMeter completely free?
It’s free, very intuitive and has all the possibilities you need to automate your work. Another big advantage of JMeter: open source. You can download the source and make modifications if you like.
Is JMeter free for commercial use?
Free of charge: JMeter is an open-source application with no license fees. Application performance testing: This application is used to perform performance tests on different types of applications, such as Web applications, web services, LDAP, databases, and shell scripts.
What license comes under JMeter?
| Screenshot of Apache JMeter 5.0 with HTTP(S) Test Script Recorder element | |
|---|---|
| Written in | Java |
| type | Load test |
| license | Apache License 2.0 |
| Website | jmeter.apache.org |
Is JMeter free to use?
Open-source â JMeter is open source software. This means that it can be downloaded for free. It is also a 100% pure Java application. Developers can use the source code, can modify and customize it according to their requirements.
Is JMeter licensed?
| Screenshot of Apache JMeter 5.0 with HTTP(S) Test Script Recorder element | |
|---|---|
| Written in | Java |
| type | Load test |
| license | Apache License 2.0 |
| Website | jmeter.apache.org |
Is JMeter free to use?
Open-source â JMeter is open source software. This means that it can be downloaded for free. It is also a 100% pure Java application. Developers can use the source code, can modify and customize it according to their requirements.
Who owns JMeter?
JMeter is an open source testing tool, developed by the Apache Software Foundation. This is a pure Java application, which can be used to measure the performance of applications, different software services, and products in both static and dynamic sources.
What is Web testing with examples?
Web testing, or web application testing, is a software practice that ensures quality by testing that the functionality of a given web application works as intended or meets requirements. Web application testing allows you to find bugs at any time, before release, or on a daily basis.
What are web tests and their types? Web Testing, or web testing is checking your web application or website for potential bugs before it is made live and accessible to the general public. Web Testing checks the functionality, usability, security, compatibility, performance of web applications or websites.
How do you do website testing?
Here are some tips for testing your website on mobile:
- Check compatibility with smartphones and tablets.
- Make sure site navigation is as simple as possible.
- Optimize your site loading time.
- Make sure the buttons are big enough for people with big fingers.
- Optimize all image sizes.
- Do not use Flash and pop-ups.
What do website testers do?
As a website tester, your task is to test and evaluate the performance of the site on the internet. In this role, you pretend to be a normal user, consider the design and usability of the site on your computer, and provide feedback about the site’s performance.
What are the 4 types of testing?
There are four main stages of testing that must be completed before a program can be cleared for use: unit testing, integration testing, system testing, and acceptance testing.
What are the 3 classifications of testing?
Let’s explore some of the most common types of testing: Accessibility testing. acceptance testing. black box testing.
What are the two main types of testing?
Although there are several types of tests in practice, but the two main categories are Functional and Non-functional test types.