Learn / Guides / Website optimization benefits

Back to guides

7 website optimization tests to improve performance

Are your users bouncing or failing to convert even though you've built an incredible website with unique features and content that responds to their needs? To identify and resolve user pain points, you need to perform website optimization tests so you can ensure a great product experience (PX).


A website optimization test is a method that helps you identify what's going wrong with your site as users navigate so you can come up with solutions to improve their experience.

This article shows you how to conduct different website optimization tests, along with which tools to use, so you can improve key elements of your website and create an amazing user experience (UX). We cover 

  1. Speed optimization testing

  2. Mobile responsiveness testing

  3. Broken links testing

  4. Usability testing

  5. A/B testing

  6. Multivariate testing

  7. SEO testing

7 website optimization tests for success 

Website optimization testing helps you understand which product changes you need to carry out to better the product and user experience and drive business growth.

In addition to using uptime and downtime monitoring tools like Pingdom or Uptime Robot to confirm your website is up and running in the first place, you can run various tests to ensure consistently smooth site performance.

Use these top seven website optimization tests to design a plan that will help you deliver a great user experience:

1. Speed optimization testing

Page-loading speed is one of the biggest reasons users have a poor experience on your website, leading to a high bounce rate and a negative impression of your brand. Too many high-resolution images, excessive videos, maxed-out site cache, and unclean code could be some of the reasons why your website's speed is slow.

How to conduct site speed optimization tests

Speed testing tools like Google PageSpeed Insights and GTMetrix are great for testing your website's loading speed across different locations, browsers, and network connections. GTMetrix will provide you with the history of your website loading speed, videos and image reports of your website analysis, and possible errors that cause delays, plus suggested fixes.

Conduct website speed tests multiple times from different locations and various connectivity networks. Focus on the regions where you have the most traffic to identify and fix any backend problems for faster loading and performance.

💡 Pro tip: even if your pages load at record speed, your users might still be displeased while browsing your site. Go beyond page speed tests with data like your total sessions, average session duration, bounce rate, and top-performing pages.

Track all these metrics and more with Hotjar Dashboards—which aggregates user behavior insights gathered from tools like heatmaps, session recordings, and surveys—to understand when users drop off during their journey and uncover the common issues they face, so you can focus your energy on problem-solving, not problem-searching.

#The site overview dashboard in Hotjar

The site overview dashboard in Hotjar

2. Mobile responsiveness testing

Imagine a user searching for a grammar tools website to help them edit emails and presentations on their phone. They find a website that offers them everything they need—but the mobile experience is glitchy, and they find themselves zooming out all the time, without a full display of menu options. 

Users will bounce pretty quickly if you don't optimize your site for mobile. Rather than disappointing mobile users or relying only on a mobile app that requires installation, run tests to evaluate and improve your website's functionality across multiple devices.

How to conduct mobile responsiveness tests

Your website isn’t going to look the same on desktop and mobile, so plan for differences like reduced icon size, vertical menu options, media size changes, and resolution changes. Before conducting a mobile responsiveness test, identify which aspects of your website you can adapt to mobile screen requirements.

Enter your website URL on WebPageTest or the Mobile-Friendly Test by Google to learn how your site looks on mobile, and identify any usability or responsiveness problems that may affect performance.

Have you ever clicked on a button only to find a 404 error page? You're likely nodding yes.

Broken links and other HTTP errors do more than just harm your brand reputation. They spoil the user experience and affect your SEO score and conversion rates. The last thing you want is to invest time and resources in creating content and optimizing your website only to find that you've been directing traffic to 404 pages.

How to conduct broken link tests

Avoid linking key content to web pages you’ll remove or disable. For example, if you have an ecommerce website and link your blogs to internal product pages that are likely to be removed when your inventory runs out, it’ll lead to a broken link. 

Schedule regular bi-weekly or monthly check-ups to ensure you know which internal or external links are broken so you can fix and redirect them for a better user experience.

Screaming Frog helps you find internal and external broken links and synthesizes your testing results into a handy, time-saving spreadsheet for a clear overview of which links are broken and where you can find them.

💡 Pro tip: fixing a broken link is usually as easy as removing or replacing it with an active one, but there are other technical errors out there you need to address to avoid user frustration.

You don’t need to be a tech wizard to be aware of these errors when they happen: Hotjar has built-in console tracking that lets you filter user data by Javascript errors. You can even watch session recordings to see the error in action and forward them to your dev team by creating a Jira issue directly in Hotjar.

#Creating a Jira issue when console tracking in Hotjar Recordings

Creating a Jira issue when console tracking in Hotjar Recordings

Bonus: monitor the prevalence of console errors with Trends and spot an uptick in errors before they cause problems by adding a widget to your Dashboard.

4. Usability testing 

Usability testing helps you test the functions of your website by observing your users and getting feedback from them to understand why they're behaving a certain way on your key pages.

Voice-of-the-customer (VoC) insights will help you make site-related decisions based on user needs and validate your web optimization efforts.

How to conduct usability tests

Begin by understanding which problems your customers are constantly complaining about through support tickets, surveys, and feedback tools.

Use Hotjar Surveys to ask questions about your website, validate changes or updates, and understand why users are dropping off or not clicking on a certain page. You can embed surveys anywhere on a page or activate them as non-intrusive pop-ups on pages you’re concerned about to collect valuable feedback without disrupting your users' browsing experience.

💡 Pro tip: if you want to fast-track the usability testing process, use one of our pre-built survey templates or try Hotjar AI for Surveys. Just enter the goal you want to achieve and watch as AI generates a survey for you in seconds.

Are you worried about the high volume of responses you might receive? Hotjar AI also generates a report summarizing key findings, quotes, and suggested next steps based on user feedback.

5. A/B testing

Improving your website performance isn't a linear process. You'll often end up with multiple ideas and different hypotheses for the best way to optimize your site. 

The solution? A/B testing or split testing. A/B tests let you experiment with two different versions of the same page to identify which performs best for your users. It’s a great place to test user interface (UI) design changes like different banners, copy options, or CTA placement or color.

A/B testing also saves you time and resources before you launch full-scale modifications by first telling you if your efforts will be worth it to improve the customer experience.

How to conduct A/B tests

With A/B tests, you only test one variable at a time. That means the first step is deciding which variable to experiment with, making sure you choose something that’s tied to your user needs and business KPIs.

Use Optimizely to run website performance tests for free and get insights on which version of your website your users prefer through its direct integration with Google Analytics. You can also integrate Hotjar with Optimizely to go deeper into your A/B testing data and get rich user insights from our interactive user behavior tools like Heatmaps and Recordings

Use Hotjar's product experience insights to go deeper into website optimization testing.

6. Multivariate testing

Unlike A/B tests, where you can only make one change in two different tests, multivariate testing lets you alter multiple variables to help you understand which combinations will get you the best results.

How to conduct multivariate tests

You can only perform multivariate testing after reaching a certain traffic volume because you need considerable traffic to test each variable and get meaningful insights. Since more than two variables will be tested, the traffic is split by the number of variables tested, and less traffic is allocated to each variable. So first make sure you’re clear on the variables you want to test and the insights you want to gain. 

Use VWO, an experimentation tool that lets you conduct multivariate tests using a simple visual editor, with room to add conversion goals, estimate test duration, and implement the tests hassle-free. 

💡 Pro tip: use insights from Hotjar’s user behavior tools to assess why certain variable combinations perform better than others. 

Analyze top exit pages with Heatmaps, Recordings, and Feedback to determine where and why users leave your site before converting, then use Dashboards to store and filter your insights by device, location, negative feedback, or top clicked buttons and links.

#Widget templates that can be added to Hotjar Dashboards

Widget templates that can be added to Hotjar Dashboards

7. SEO testing

Search engine optimization (SEO) is a crucial aspect of improving your web performance. After all, if you don't rank on the search engine results pages (SERPs), how will potential customers find you?

SEO testing lets you check which keywords, titles, meta descriptions, or links will help you achieve your goals and improve overall site performance.

How to conduct SEO tests

First, focus on creating well-optimized content, building backlinks, and applying SEO best practices to drive more traffic to your site.

Then, use tools like A/B Tasty for in-depth SEO testing. You can create different versions of your web page to compare title tags, header tags, linking, layouts, copy length, images, and CTAs.

For example, if you want to improve the click-through rate (CTR) on one of your product pages, you can test the effect of a change in the title tag on the number of clicks you get.

Leverage website optimization tests to improve performance

There are many ways you can optimize your website, but your users' needs should be the foundation of all your optimization efforts. Testing your website's optimization practices helps you identify blockers, drop-off points, and functionality issues that keep users from accomplishing their goals on your key pages.

The key is to adopt an approach that considers all the key stakeholders in relation to your website, from the users down to the search engines crawling your pages. You should aim to make the optimization process continuous, experimental, and impact-driven to ensure that you maximize the potential attached to your budget and resources.

Sean Potter
Senior Growth Manager, Hotjar

Use Hotjar to go deeper into website optimization testing

Learn how product experience insights tools can help you focus your website optimization efforts.

FAQs about website optimization tests