How fast does my site load? This is one of the central questions in performance, UX and search engine optimization. When answering this question, you should rely on the right tools. Because only a few tools provide really good data. Today I'll introduce you to the three most powerful ones and show you how to use one of them, Pingdom.
There are some great overview articles on the web about tools with which every user can measure the performance and loading time of their own website very easily and, above all, free of charge. These overviews are very helpful, but often make a mistake that can lead to more confusion than clarity for users. They compare two to three completely different types of tools with each other and sometimes do not go into enough detail about the differences.
This can then lead to users trying to make performance comparisons with completely unsuitable data. This is a pity, because measuring with the right tools saves a lot of time and trouble.
Every user who wants to measure the performance of his siteshould know one difference: the difference between potential analyses and such tools that measure the loading time of a website. The first group includes tests such as Google PageSpeed Insights and Yahoo's YSlow. These tools indicate how well the tested website meets the requirements for a fast page load. Both thus provide excellent input for onpage optimization. However, such tests explicitly do not measure the loading time of your website.
But most of the time that's exactly what you want to know: How long does my site take until it is built up, until the customer can interact with it, until I earn money? And here's the rub: as far as we know, there are actually only three free tools that provide really good data:
Therefore, in this and two other articles, I will show you what the three measurement tools can do, how to use them and how to interpret the data so that you can get the most out of the measurements.
Three features make a measurement tool particularly valuable: setting options, level of measurement detail and variety of data
The tools I mentioned are so good because they provide particularly valuable data. This means that the measurement results:
- Can be adjusted through various setting options.
- Be output in a high level of detail.
- Consist of the results of several measurement methods that can be compared.
In practice, this means that with a good measurement tool you can set how it measures the loading time of the website. This is usually the choice of the test server and its location and sometimes also the choice of the test browser.
The level of detail of the data means that not only time information is given, but also a detailed description of what was actually measured. Two tools may well understand something different under "loading time". Of course, it is even better if standardised terms are used, such as time to first byte.
And finally, it is good if not only the loading time of your website is measured, but also information on the number of HTTP requests, the size of the loaded data packets or the results of potential analyses are displayed at the same time. This way, you can quickly see which adjustments you can make to optimise the loading time.
Other tools known to us offer such possibilities only to a limited extent or not at all and can therefore lead to problems of understanding and thus interpretation. For you as an end user, however, these advantages mean a decisive disadvantage: the data is not nearly as easy to understand as, for example, the results of Google PageSpeed Insights.
Measurement data are not always easy to read - but with some basics they can always be understood
The most daunting part is certainly the so-called waterfall diagram. But it is precisely this that provides particularly important data. It is therefore worthwhile to take a closer look at this type of diagram.
In this post, I will first explain Pingdom in more detail. This is a tool that can quickly provide very informative information about your site and also measures the loading time of your website.
- Input mask from Pingdom. This tool is one of three that we think gives really good results and especially measures the loading time of your website.
Pingdom shows very nicely in which order your site is built and how big the individual building blocks are.
Pingdom is fast and very easy to use. In principle, you only have to do two things:
- first enter the domain to be tested
- then select the server location
The server location - in addition to the choice of browser to be tested - is one of the most important settings to be able to understand how and how fast your site builds up for customers from different regions. In such tests, the server location indicates from which location your website is accessed for the speed measurement.
Always make sure to use the same server location, especially for performance comparisons. This is the only way to compare the results. If the loading time of your website is measured once from the USA and once from Frankfurt, the loading times for a visitor from Germany will differ significantly.
- Selection options for the test server of the Pingdom test.
When you start the test, three large data packets are ejected after a few moments:
- Overview and the result of the potential analysis
- Detailed breakdown of the site
- Waterfall diagram
Right at the beginning, the three most important key data for understanding the performance of your site are given out:
- the grade of the potential analysis (1)
- the loading time of the site (2)
- the number of HTTP requests (3)
The rating is supposedly based on Google PageSpeed Insights. In all our tests so far, however, this value has been distorted (in this specific case 15 points below the original rating and also significantly below the rating for mobile devices) and thus unusable.
The loading time (2) of site is the central parameter with which, for example, performance comparisons can be made. It is the direct answer to the question: How fast does my site load? The number of HTTP requests (3) is also well suited for such comparisons. The following applies here: the fewer HTTP requests, the better.
A nice addition is the "Faster than" component (4). In our case, this indicates that raidboxes.de is faster than 75% of the other pages tested at pingdom. This information can be used for approximate localisation. If, for example, you see that your site loads faster than 95 per cent of the other pages, then this is already a first indication that your site is damn fast.
The "Performance Insights" section is also part of the overview. Here you are presented with evaluations and suggested solutions for various performance-relevant aspects of your site . Very similar to the tools from Google or Yahoo. It is important to understand that the loading time of the website was not measured here, but the potential for optimising the loading time.
- As the second part of the load time measurement, pingdom also outputs this potential analysis.
The second section is the detailed breakdown of site. Here you will mainly get information about two central characteristics: The functionality of the individual pages and the composition of the site.
For example, in the area you see below, you would see all 404 errors of your site . In our test case, you can see here that 69 responses from the server to the browser took place normally. Two of these requests were forwarded.
- Pingdom also checks how many redirects, 400s and 500s errors are produced by your site .
In the areas below, the HTTP requests and the content of your site are broken down by type and source. In this way, you can quickly see whether a certain type of content, such as images, is consuming a particularly large amount of space or is producing a particularly large number of requests and thus slowing down your site .
In our case, the scripts take up a lot of space and cause many requests. (1+2) This is mainly due to our support tool, Intercom, the Trusted Shops badge and requests from site itself. (3) In conjunction with the requests, you can also see: The requests sent by intercom refer to particularly large data packets. (4)
- Breakdown of site by requests and size of data packets.
The waterfall diagram now shows you in detail the order in which the requests run and how long each request takes to load. This means that the waterfall diagram is a detailed view of the loading time of your website.
You will also find a legend at the very end of the test results that explains what the symbols and colours mean.
In our case, you see at the top the redirect from http to https (1), then the first contact with the server (2) and then the loading times of the individual scripts (3).
- The waterfall diagram of pingdom.
Pingdom also offers the possibility to display exactly which parts of a request take how long to load. This allows you to determine the time to first byte (i.e. the time the server needs until the first data packet is sent), but you have to collect it from the individual values.
Example: If you look at the first request of our site , you will see that it takes a total of 129 milliseconds. It consists of a DNS lookup, which takes less than one millisecond, a so-called SSL handshake, which takes 29 milliseconds, the connection between the browser and the server, which takes 52 milliseconds, the sending of the data from the browser to the server, a waiting time of 47 milliseconds and finally the reception of the first data.
- Detailed view of the waterfall diagram. If you want to measure the loading time of your website, you can see exactly how long certain data packets take to load.
During the specified waiting time, the server calculates all necessary PHP processes. This value is therefore well suited if you want to compare two hosting providers.
In this way, you can look at each individual request and compare it with another measured value. In this way, you can determine whether the loading time of your site has improved after an optimization measure and, if so, by what factor.
Advantages: Pingdom delivers relevant data very quickly, with high information value
Overall, pingdom is a good tool to measure the loading time of a website. You can quickly tell with pingdom:
- how fast a site loads
- how big it is
- where it still has potential for optimization
- how this potential can be harnessed
- how to build your site
Disadvantages: Especially the indication of the loading time is very inaccurate
However, the tool has two important limitations: Firstly, only very few server locations are available for testing. This is not a disadvantage per se, because if you always measure with the same server, the results are perfectly comparable. However, this is exactly what you should pay attention to when using the test. You should also choose a server location that is as close as possible to your main visitor group.
Secondly, the loading time of site is only shown in aggregated form. This means that you cannot see which value the 1.84 seconds from the example refer to without looking at the waterfall diagram. Also, no distinction is made between the cached and uncached version of site .
Probably the biggest disadvantage of Pingdom is that you cannot see the perceived loading time. This is because your site may take ten, twelve or thirteen seconds to load, but after only three seconds it appears to be completely loaded. Your site would thus be perceived as much faster than it is. Pingdom, however, does not offer the possibility to display this perceived loading time (in the free version, mind you). GTmetrix and webpagetest.org can do that better.
Pingdom can quickly answer what is often the most important question: How fast does my site load? The tool also reveals a lot about your page structure. But it can be even better! In the next part of this series, I will take a closer look at GTmetrix. This test provides even more data and is particularly convincing with a video function and a time series analysis of your page load time.
Which tools have you had the best experience with in performance analysis so far?