Understanding Key Metrics
There are many different data points that can be collected via web analytics. Some of these data points, or metrics, might be familiar to you; others may not. To that end, Table 1.1 details some of the most important of these metrics and what they measure.
Table 1.1. Key Web Analytics Metrics
Metric |
Description |
% exit |
The percentage of users who exit from a given web page as a share of pageviews. |
Bounce rate |
The percentage of visits in which the visitor enters and exits on the same page, without visiting any other pages on the site in between. |
Click |
A single instance of a visitor clicking a link from one page to another on the same site. |
Click path |
The sequence of clicks that website visitors follow on a given site. |
Click-through rate (CTR) |
The percentage of people who view an item and then click it; calculated by dividing the number of clicks by the number of impressions. |
Depth of visit (pageviews per session) |
The average number of pageviews a visitor initiates before ending his session; calculated by dividing the total number of pageviews by the total number of sessions. |
First visit |
The first visit from a visitor who has not previously visited the site. |
Hit |
A request for a file from a web server. Note that a hit is not the same as a pageview; a single page can have multiple elements (images, text boxes, and so forth) that need to be individually loaded from the server. For example, a web page that includes four images would result in five hits to the server. |
Impression |
A single display of an advertisement on a web page. |
Loyalty |
A measurement of how often visitors come to a website, calculated by dividing the total number of sessions or visits by the total number of unique visitors. |
New visitor |
A visitor who has not made previous visits to a website. |
Pageview |
A display of a complete web page. One visitor looking at a single page on your site generates one pageview. (Pageviews typically don't include error pages, or those pages viewed by web crawlers or robots.) |
Pageview duration (time on page) |
The average amount of time that visitors spend on each page of a website. |
Repeat visitor |
A visitor who has made at least one previous visit to a website. |
Session |
A series of pageviews from the same visitor with no more than 30 minutes between pageviews—and with no visits to other sites between pageviews. Unlike a visit, a session ends when a visitor opens a page on another site. |
Single page visit |
A visit from a visitor where only a single page is viewed. |
Time on site or length of visit |
The average amount of time that visitors spend on a website each time they visit. |
Unique visitor |
A visitor who visits your site one or more times within a given timeframe, typically a single 24-hour period; a visitor can make multiple visits during that timeframe, but this counts as just a single unique visitor. For example, a user visiting your site twice in one day is counted as a single unique visitor. |
Visit |
A series of pageviews from the same visitor with no more than 30 minutes between each pageview. Unlike a session, a visit continues (for 30 minutes) even after a visitor leaves your site. |