Over the past couple of months, as we rolled out  a new Site Monitoring service to customers, one question we?ve heard a lot is, ?what ARE typical values for the various metrics??  For example:

• What?s a typical value for Time to Interact?
• What?s an unusually high Time to First Byte?
• Does my site have more CSS files than a typical site?

So, we thought it?d be useful to share some recent empirical data.  Below is a summary of metrics for 14,000 web sites measured by Yottaa?s global site monitoring service.  (For a summary of what these metrics are, why they matter, and the insights they provide, check out this eBook.)

To get insights into the overall distribution, in addition to the median (50th percentile) value we also provide the 10th and 90th percentile.  So for example, the median Time to Interact is just over 6 seconds (6,248 msec), and if a site is faster than 2.75 seconds, it would be in the top 10% of sites; similarly, the typical page?s DNS resolution time is just 64 msec, and a DNS connect time slower than 255 msec would be among the slowest 10% of sites.

Ways to Use This Data

There?s a number of ways our customers are using these metrics:

1. Establishing a baseline ? does the site have problems/anomalies today?
2. Comparing themselves to the general population ? how are they different/better/worse?
3. Benchmarking against competitors or other relevant players in your ecosystem
4. Using this as input for defining thresholds for issue definitions in a site monitoring service (from Yottaa, or another enterprise-grade monitoring service)

In the near future, we’ll be sharing a lot more data, including slicing/dicing it for specific industry segments, and correlating the various factors.  As a preview – here’s just a couple data points:

Impact of Image Size on Page Speed

Impact of Javascripts on Page Speed

Impact of CSS Files on Page Speed