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Today Rigor is launching an awesome new way to track and trend your web performance to ensure you get fast and stay fast: Performance KPIs.

We all know that performance of your site directly impacts your business. But different types of companies, and even different departments inside the same company, have different metrics they need to keep an eye on. For instance, IT/Ops looks at uptime and first byte time, or advertising teams track onload and fully loaded, since those typically define when ads can appear.

With Rigor’s Performance KPIs, everyone can collect, track, trend, and alert on the performance metrics that are most important to them.

Your Performance KPIs All in One Place

Let’s use an example to see the insights that Performance KPIs can provide and how that can speed up your workflow. We start with the traditional monitoring history graph for online retailer Lilly Pulitzer. Rigor’s check history graph shows us whether a site loaded successfully and how quickly it loads from locations all over the world.

You can see measurements where the load time has been slower than our target, but it is not immediately obvious why.

This is where our new Performance KPIs come in. With Performance KPIs, we can overlay different performance timings on the same graph to better understand what timings are fast, and which ones are slowing down the experience. Here is the graph with the first byte time, the DOM load time, and the window.onload time:


We see that the first byte time, represented by the blue line, is consistently fast. So, we know there are not network or server problems. The DOM load time, represented by the black line, is also consistent and fast. As such, it is clear that there is not a problem loading the base HTML page. However, we see that the onload time is slow. This means something is happening after DOM load time, that is delaying the window.onload event. Could it be that the Lilly Pulitzer site is serving a bloated or misconfigured asset for just to users in the Chicago area?

To find out, we leverage another measure of the Performance KPIs graph: The ability to graph different categories of data at the same time. In this case, let’s overlay the total size of content being load:

The total size is largely holding steady at 5.3 MB. Something is blocking the onload event and we know it is not a bloated resource. The most likely cause is that there is a request in the waterfall that is blocking the load event. On an eCommerce site, the culprit is probably third party JavaScript that is being loaded synchronously, instead of following the best practice to asynchronously load the script.

To confirm this, we can click on the graph’s data point and view the waterfall:


The blue vertical line on the left is DOM load time, and the red line on the right is the window.onload time. The issue that is pushing out the window.onload time is a third party JavaScript file. The Lilly Pulitzer site is not asynchronously loading the third party JavaScript, so it is blocking the waterfall and nothing can happen until it fully loads.

More Metrics for Deeper Analysis

As we can see from the Lilly Pulitzer example above, the ability to overlay different types of metrics is instrumental in surfacing the source of performance issues on a site. To help support this, Rigor has greatly expanded the number of metrics. Rigor now collects 23 different metrics on each page load. This includes everything from timing information like DOM load time or fully loaded time, to performance budget metrics like the size of CSS content, to error information like bad server response codes.

The full list of metrics and their meaning is available in our knowledge base.

Trending Key Performance Metrics Over Time

While collecting rich performance data and comparing different performance runs is useful for tracking down the cause of performance problems, but it’s also beneficial to get a high-level view of your performance over time.

Let’s imagine you are the head of development for a media company. You understand the impact of performance on the user experience, and thus your business metrics page views and ad impressions. In the last quarter, you have launched a front-end performance initiative. Your team has been implementing common performance optimizations. You have also spent time and money training your developers to understand front-end performance techniques so they avoid introducing new performance issues when they create new features. How do you measure whether this performance initiative was successful?

This is where the trending feature of Performance KPIs comes in. You can “zoom out” and see how your key performance metrics have changed over time. What is your page load time? How has that improved relative to last week, last month, last quarter, or even last year?

With Performance KPIs, Rigor can aggregate the median, minimum, or maximum of any performance metric into hourly or daily rollups and graph those over time. This helps you track progress and ensure your site and apps are improving performance over time without getting lost in minute-by-minute differences.

APIs for KPIs

The ability to collect and display rich performance metics about your websites and apps, as well as view and trend that data over time, is certainly valuable to customers. However, this data becomes even more valuable when you can integrate it into other systems, or overlay it with business data or other analytics.

This is why all the performance data you can see in our Performance KPIs graph is also available via our versioned, RESTful API. You can benefit from all our great work, even if you never log in to see it via our UI.


Excited about getting started with Performance KPIs? Great. For existing customers, we have a guide showing you how to use Performance KPIs in our knowledge base.

Do you need to have visibility into performance timing metrics like DOM Content loaded Fully Loaded or performance budget statistics like the number of fonts being loaded or the size of all of a page’s JavaScript? Then you will love Rigor Monitoring and our new Performance KPIs.

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