Metrics and dimensions are fundamental building blocks of all reports. Understanding the difference between metrics and dimensions, is critical knowledge for an analyst.
In this post I'm going to answer the question, what is a metric in Google Analytics, and help you use this knowledge to better communicate as an analyst.
In this post you will learn the following:
- What is a metric in Google Analytics
- What is a dimension in Google Analytics
- Examples of metrics and dimensions
- The most important metrics in Google Analytics
What is the difference between a metric and a dimension?
What is a metric?
A metric is a quantitative measurement of something we care about.
In other words, a metric is a number. It could be a whole number or a fraction.
If you're familiar with Google Analytics then the number of sessions to the website in a given timeframe would be a metric. Other examples of commonly known metrics in Google Analytics are pageviews, bounce rate, time on site, pages per session and % new sessions.
What is a dimension?
A dimension is a specific attribute which we can see to segment our data. A dimension is typically represented as a text or date attribute and used in conjunction with a metric.
The best example I can think of is the country dimension. In Google Analytics it is possible to segment sessions, page views and other key metrics by country. Country is a text value.
The screenshot above shows a breakdown of users, new users and sessions by the country dimension.
Notice how in the first screenshot I posted we have single values for our metrics. When we use a dimension in Google Analytics we take the single value and break it down by the dimension.
When we do this we can view the breakdown both in absolute terms (444 sessions to India), and percentage of total (12.05% of all sessions came from India).
The most important metrics in Google Analytics
If you are new to Google Analytics then you will need to start learning the different metrics. To make your life easier I've included a list below of the most important metrics in Google Analytics. The entire list of metrics is quite long but not all metrics are important to track.
Sessions is the most standard metric in Google Analytics. Since Google Analytics tracks visits to your website, a session is the "container" where all other data is contained.
When someone visits your website a new session is created. A session should be viewed as a "visit".
If the number of sessions to your website is growing then you're site is growing in popularity.
Users is the next metric you will need to know. The users metric represents the number of unique devices which visit your site. I specifically mention devices because technically if you visit a website from both your phone and computer, you'll be counted as 2 unique users in Google Analytics.
For this reason I prefer to track sessions and more or less ignore the users metric.
The one exception is when looking at new vs. returning users. If your site has a high return user rate then you may want to track new users closely since your sessions might be going up but the number of new users to your site isn't growing as much.
The pageviews metric is quite self explanatory. It represents the number of pageviews that take place in all your sessions. Since a page could be viewed multiple times in a single session it is important to note that the pageviews metric includes all pageviews.
Bounce rate is a unique metric which confuses a lot of analysts. In short bounce rate is the percentage of sessions where only one page was viewed during the session.
The term comes from "bouncing out of the website". If you visit a website and then hit the back button or close the tab then that session would be considered a bounced session.
Most websites have a high bounce rate (>70%) since typically people visit websites to get specific information and then move on with their lives.
The ideal bounce rate for a website depends on a number of factors from industry to website look and feel, and even loading time.
So what is a metric in Google Analytics?
A metric is a quantitative value that we want to measure, track and analyze so we can make data-driven decisions for our business.
As an analyst, it's important you know the differences between metrics and dimensions and know how to breakdown your metrics by different dimensions.
If you would like to explore this topic in more detail then I recommend this article written by Google - Dimensions and measures.