Key Takeaways

  • Load testing is an essential part of any serious DevOps plan and should be conducted regularly.
  • Load test metrics help development teams isolate issues with websites and web applications and to work efficiently to provide the best possible experience for users at scale.

If you go into the load testing process without a clear idea of what you’re looking for, it will inevitably result in confusion when you look at your test results. It’s essential to have a good understanding of what your load testing results mean before you and your development team can go forward and implement changes and make meaningful improvements for your users, which, in the end, is what load testing is all about.

This post will help guide you through to making your website seamless and exceptional for your users at scale, across devices, and around the world.

load test metrics

The Benefits of Regular Load Testing

Some of the benefits of regular load testing are demonstrated in these statistics:

  • Shopzilla reduced page load times from 7 seconds to 2 seconds and saw a 7%-12% increase in conversion rate
  • They also increased pageviews by 25% by decreasing their load time by 5 seconds
  • and were able to support the same volume with 50% (402 to 200 nodes) less nodes, cutting server costs in half
  • If Amazon increased page load time by +100ms they lose 1% of sales(+100ms === 1 marketing pixel / third party script)
  • If Google increased page load by +500ms they get 25% fewer searches
  • If Firefox reduced load times by 2.2 seconds they saw an increase in download conversions by 15.4%
  • Netflix saw a 43% drop in outbound traffic after enabling compression
  • 52% of online shoppers claim that quick page loads are important for their loyalty to a site

These are only a few things you need to be on the lookout for. For a more in-depth analysis, read further in this article and learn more about load test metrics.

Load Testing Metrics to Know

Performance metrics can keep an eye on your website’s performance. You need to be able to tell how the website behaves on the user’s end, as well as know how much volume your servers can handle. There are different metrics for each.

Average Response Time

The difference in time between when the user first creates a request, and the end-time when the result is delivered is averaged out to give the “average response time”. Learning a website’s average response time can be critical to the success of your load test, and in turn of your business.

Users prefer a fast-acting website, and will quickly jump to competitors if your website’s service slows them down. Learning the website’s average response times will give you insights into the performance of your servers. It will tell you whether you need to invest in a more efficient one, or to recalibrate your current one to give you the results you need to succeed.

Some studies of visitors’ experience and confidence have shown that in England, 67% of online shoppers are likely to abandon purchases on a slow website. Improving a website load time by even one second can improve ecommerce conversion rates between 10-20%. Beyond this, an Online Retail Performance Report made by Akamai in 2017 shows that up to half of all consumers browse for services and products on their phones and that even a short, 100ms delay can hurt conversions by 7%.

In short, response time is essential both for ecommerce and online lead generation. Users have millions of options at their fingertips, and if your website or web application is slow-performing, you’re likely losing revenue as a consequence.

Peak Response Time

If average response time gives you an overview of your website’s performance, peak response time will give you insights into specifics. Peak response time is the measurement of the longest time taken by your server to generate a response to a user’s request. Knowledge of peak response times will answer questions related to specific components that may have been worrisome.

It’s vital to the survival of your website to measure peak response times. If an ill-functioning proponent lingers for too long, the results can be devastating for your system in general and for your business as a whole.

Slow websites see decreases in traffic. Google reports up to 53% of users are likely to abandon a website that takes more than three seconds to load. Beyond five seconds, the likelihood of a user abandoning a page increases to 90%. At 10 seconds, the probability of a bounce increases a massive 123%.

Slow sites also hurt conversions and decrease the likelihood a user will visit and purchase again, with downstream effects on revenue that can last for years. Even worse, Google and other search engines understand that slow-performing sites are terrible for users’ experience, so slow sites are given lower rankings in their algorithms. Not only will fewer people see your slow website, they’ll be less likely to remain on it and even less likely to return.

Error Rate

The error rate comes out as a ratio between successful and unsuccessful requests. For every 100 requests, if five errors arise, the error rate comes out as five percent. You can anticipate errors to increase in proportion when the website comes closer to its capacity. The error rate of your website will tell you how efficient your website is.

Your error rate will determine whether your website will perform over the long-run. To make your website successful and sustainable, it’s impeccable that you load test it at regular intervals. Load testing periodically will give you multiple coordinates with which you can graph how the performance of a website changes under low and high loads.

Concurrent Users

This metric measures the website’s performance relative to the number of users active on it at any given moment. This becomes especially important for websites that anticipate a large number of users to sign on simultaneously. Such a scenario may arise for a streaming website, for instance, when a World Cup match is streamed.

The metrics for concurrent users are slightly different from those of Requests Per Second (RPS). RPS measures the number of requests sent to the server whereas concurrent users is a measurement of the number of users present on a website as a whole.

Having an idea of concurrent users gives you a sense of reality. In a real world production environment, there will be multiple users on your website at the same time. Each will have their unique behaviors, and this increases the complexity with regards to testing. At the same time, the more complex the behaviors a load testing tool can emulate, the more real its results.


Throughput is a measure of the number of requests a given application can accommodate in a specific time (second, minute, or hour). Before beginning any test, it’s important to set a realistic performance throughput goal in order to achieve precise and reliable results. Throughput gives you an idea of how much data moves between your servers and the user’s device. Measuring throughput will give you an idea of how much bandwidth you need to accommodate your users. It’s vital to understand just how much bandwidth transactions consume. Load testing will help you understand just that.

load test metrics

Use LoadView for All Your Load Testing Needs

LoadView is the industry-leading load testing platform for websites and web applications and offers great readability for metrics, so you can quickly load test and get human-readable results you and your development team can turn into actionable improvements for your users.

Now that you have an idea of what performance metrics you should look out for, you can start load testing your website. We know you can’t wait, so we offer a free trial to help you get started. If you’re not convinced with our free trial, you can also book a one-on-one demo.