What is a “metric” in Google Analytics?
The dates in your date range.
A dimension that can help you analyze site performance.
The numbers in a data set often paired with dimensions.
A segment of data separated out in a report for comparison.
Explanation:
Metrics are quantitative measurements. The metric Sessions is the total number of sessions. The metric Pages/Session is the average number of pages viewed per session.
Read more here: https://support.google.com/analytics/answer/1033861
Every report in Analytics is made up of dimensions and metrics.
Dimensions are attributes of your data. For example, the dimension City indicates the city, for example, “Paris” or “New York”, from which a session originates. The dimension Page indicates the URL of a page that is viewed.
Metrics are quantitative measurements. The metric Sessions is the total number of sessions. The metric Pages/Session is the average number of pages viewed per session.
The tables in most Analytics reports organize dimension values into rows, and metrics into columns. For example, this table shows one dimension (City) and two metrics (Sessions and Pages/Session).
In most Analytics reports, you can change the dimension and/or add a secondary dimension. For example, adding Browser as a secondary dimension to the above table would result in the following:
Valid dimension-metric combinations
Not every metric can be combined with every dimension. Each dimension and metric has a scope: user-level, session-level, or hit-level. In most cases, it only makes sense to combine dimensions and metrics that share the same scope. For example, Sessions is a session-based metric so it can only be used with session-level dimensions like Source or City. It would not be logical to combine Sessions with a hit-level dimension like Page.
For a list of the valid dimension-metric pairs, use the Dimensions and Metrics Reference.
How metrics are calculated
In Analytics, user metrics are calculated in two basic ways:
As overview totals
where the metric is displayed as a summary statistic for your entire site, such as bounce rate or total pageviews.
In association with one or more reporting dimensions
where the metric value is qualified by selected dimension(s).
The following diagram illustrates these two types of calculations with a simple example. On the left side, user data is calculated as an overview metric, while the same data is calculated via the New User dimension on the right side.
In the Overview Report example, calculations for time on site are computed using the time difference between each user’s initial session and the exit, with the sum of each session length averaged across three sessions. This number is based on a relatively