#30DaysOfWebPerf: The Pros and Cons of a Twitter series
My experiment with 30 days of web performance tips. All packaged up for your temporary viewing pleasure.
What tools are web performance engineers using to measure site speed in 2021? Learn which are the most used tools as well as some new tools to try out.
Sometimes it's hard to discover all the great web performance measurement tools out there. What are performance engineers using in 2021? What tools do they want to use?
I set out to answer these questions by creating a survey. I shared this survey with the web performance engineering community. It's not statistically perfect (27 responses), but I still found it insightful. I also learned a lot for next year.
This post will cover:
The survey asked one question about a large list of tools, "Which tools do you know about and use?" Respondents chose one answer that described their experience with it:
Find the full list of tools in the results section below.
These three open-ended questions were also asked at the end:
Now let's jump into the data!
Combining the data from the first two columns ("I use this tool regularly" and "I use this tool sometimes") yields a list of the most used tools:
We can see that WebPageTest and Chrome dominate the list of the top tools. Yet, Qualys' SSL server test and Cloudinary's image analysis tool fill important gaps.
I appreciate that one of the top tools is not a tool at all: turning JavaScript off in the browser settings and seeing what happens on page load.
Digging deeper into the most used tools, the ones performance engineers reach for the most often are:
This category had clear leaders. Only these tools had 25% or more respondents say that they used them regularly.
This category had a lot of ties and steadily declining distribution. This group represents those used sometimes by 33% or more respondents. Be sure to check all results to see more tools.
This is an interesting category. It's the set of people who do not already use this tool but would like to. This suggests to me that they see the potential value but something is stopping them. The hurdles could be:
I bet an opportunity exists for more documentation or learning resources for these tools. I wrote Explore JavaScript Dependencies With Lighthouse Treemap because of this data!
The stacked bar chart below shows the full results. Also, you can find the raw data in this Google spreadsheet.
One of the open-ended questions asked respondents which other tools they thought were great. I'll be sure to add these to the survey next year:
Real-user monitoring seems to be a theme here. Some are paid tools with nice tracking and dashboards. Others are iterations of how to access the Chrome UX Report data for a particular site (Core Web Vitals).
The favorites data can be summarized with the following quote from the responses:
WebPagetest, WebPagetest, WebPagetest. It's just an amazing tool, it does loads of stuff, and it's constantly improving.
WebPageTest was mentioned by 70% of the respondents. That number jumps up to 86% if you only include people who answered the question. No other tool came close, but here are the top 5:
For this question, most people were happy with all tools. However, some concerns are valid though it's not always about the tool itself. Here are a few quotes:
PageSpeed Insights - This tool is both a blessing and a curse. It's a blessing because for developers it has a lot of useful information if you know how to read it. But we have a lot of non-developers who just look at the score and judge by that.
Lighthouse is the engine behind the PageSpeed Insights scores and recommendations. I both love and semi-dislike Lighthouse for the same reason. Even developers can focus on the top score at the expense of everything else. Lighthouse is great for people newer to performance because so many learning resources are connected to each audit. But, we need to get past focusing on "Lighthouse 100".
Lighthouse and WebPageTest: If you use Lighthouse you supports Chrome monopoly and the Googles surveillance capitalism. I really liked WebPageTest when it was Open Source. Now it's got a non Open Source license and backed by venture capitalists. Every issue you create, every move you make with that tool, you help those venture capitalists to make more money when they sell Catchpoint.
Another comment lamented the US-focus of PageSpeed Insights. We need to be mindful of a website's target audience. If it's a non-US country, then testing from the US is never going to yield results in line with real user experiences.
A few mentioned the Chrome Coverage tool. Different user journeys could use different parts of the code. I always give a caveat with this tool because once you start interacting with the page, the JS and CSS usages increase.
I think this was a great starting point for a survey of this type. In the future, I'd like to:
Are these results in line with what you expected? Was anything surprising? Do you have suggestions for next year? Let me know on Twitter or in the webmentions!
I'm a freelance performance engineer and web developer, and I'm available for your projects.
Hire meMy experiment with 30 days of web performance tips. All packaged up for your temporary viewing pleasure.
Add Prettier with a pre-commit hook and dedicate one commit to a full reformat
Discover all JavaScript downloaded for a site and used vs unused in a handy data visualization.
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Great post Sia, thanks for sharing π source
Thanks! source
Great post, thanks! I hope that the variety of tools available will one day allow us to make the web more efficient. However, we've been advising for 15+ years to optimize images and it is still not done. It's not about the tools, it's about the governance of the projects. source
Building more tooling for tech people is great, but we really need to up our game and convince the business with revenue success cases. Our market is not yet mature, we still have a lot of room for improvement. source
Totally! I've found increased interest because of the SEO impact now which is nice. source
SEO has made a breakthrough, but only because it has released budgets to "pass" the Core Web Vitals, like taking an exam by cramming. On the long run, you need long-terme sponsorship, training, transversality, monitoring capabilities and a business commitment to qualitative UX. source
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