Knowing your website's speed performance can give you a huge advantage. To better understand your results from our speed test tool, keep on reading.
1. Did your website score an A+ Ranking?
If so - congratulations, your website speed is outstanding! But, don’t be demotivated if you didn’t. Speed optimization is a journey. Keep optimizing your website and the results will speak for themselves.
2. What metrics does our website speed test tool measure?
To give your website a Final Score Grading, our website speed test tool measures exactly 3 things:
The latter 2 are components of the Core Web Vitals that Google uses to determine your website’s performance.
Metric #1: Server Response Time
Server speed, which is your web hosting service, is pretty much the heart of your website. How fast your website actually does anything is dependent on how fast your web hosting service is. We measure server speed by how long it takes (in milliseconds) for the server to respond to requests.
When you key in the URL in our tool, it pings your site from our 10 global nodes and measures how long it takes for your server to respond to these requests from around the world. This emulates 10 different people in different locations accessing your site at the same time. The end result is the worldwide average of your server speed, in milliseconds.
Metric #2: Largest Contentful Paint (LCP)
We measure LCP because we know that Google prioritises good user experience for their ranking, and slow load speeds don’t exactly count as good user experience. To measure LCP, Lighthouse checks to see how long the largest visible element on your site takes to load (in seconds) and ranks that time. This is done automatically via the Lighthouse API which we have incorporated into our website speed checker tool.
Metric #3: Total Blocking Time (TBT)
TBT works by measuring the estimated total amount of time your browser is blocked when a site is being loaded. Loading images, text, Javascripts, and everything else, draws power from the CPU, which blocks your browser from doing more. By estimating the amount of time your browser is blocked because it’s loading something, Lighthouse can measure how good the user experience is. The less time your browser spends being blocked, the better the user experience.
TBT is measured to give us an idea of First Input Delay (FID). We don’t measure FID directly because FID requires actual user data which can’t be simulated. Since TBT is lab data that CAN be simulated, and good TBT scores naturally improve FID, we’ve chosen to measure TBT instead.
Why don’t we measure Cumulative Layout Shift (CLS)?
That’s because CLS measures visual stability and has nothing to do with speed. We want our website speed test tool to be specially dedicated to measuring website speed, so that our users can more accurately diagnose which part of their website is slowing them down - the web hosting, or the coding. Hence we’ve decided to leave CLS out completely.
3. How do these measurements contribute to your website Final Score Grading?
We use the results from our server speed test combined with the numbers from the Web Vital metrics, and convert them into a percentage. The percentage results from these 3 metrics are then averaged out to provide us with the server’s Final Score Grading, which is ranked below:
Obviously, you’ll want your Final Score Grading to be at A+ to ensure your site performs exceptionally well for users and to increase your chances of getting ranked on Google searches. At worst, you’ll want it at no less than a B. A good score will show up as green, a moderate one as yellow and if it’s bad, it’ll be red. To get an A+ rating, you’ll need all three metrics to show up as green.
3.1 Server Response Time ranking system
As we’ve said, our 10 global nodes will ping your website and tell us how long it took to respond to each one of their requests.
We use these numbers to calculate a Global Average which is then rated accordingly:
The ideal Bitcatcha speed rating for your server speed result should be Good (180 ms and below). The ratings from our server speed metric provide you with a very good reference on how fast your web hosting service is.
3.2 LCP & TBT ranking with the Lighthouse API
Lighthouse (which is Google's tool to test Web Vitals, incorporated into our website speed checker) measures the LCP in seconds.
If the largest piece of content is loaded within:
TBT measures the amount of time your browser is blocked in milliseconds:
These metrics will then provide you with a Final Grading Score which ranks your website on a scale of A+ all the way to E. You’ll want to ensure that your website gets at least a B+ ranking, or you’ll suffer from a drop in conversions/sales and Google rankings due to slow site load speeds.
4. How can you improve your Final Score Grading?
By improving all of these 3 metrics! Make tweaks until all 3 metrics are green, and you’ll get that coveted A+ ranking. To learn exactly how to do that, check out our full article here.
5. How well are other websites performing?
Now that you’ve tested your website speed, why not see what you’re up against? We used our website speed checker to grade the performance of the world’s most popular websites. Check out our results page for the top 100 websites.
We've purchased web hosting accounts for each host, then set up test sites and tested their server response times. See how each host performs in the respective locations below:
