Key metrics, explained simply

When you open Google Analytics, you are immediately confronted by numbers and terms that can feel like a foreign language. This guide decodes the most important ones and explains what they actually mean for your business.

Users, sessions and views

These three are the volume numbers, and they're the easiest to mix up:

A user is a person (or more precisely, a browser/device) that visited your website. The "Users" column in most GA4 reports shows active users, not everyone who loaded a page.
A session is a single visit. One user can have several sessions, and a session ends after 30 minutes of inactivity by default.
A view is recorded every time a page loads, so one visit can include several views.

What they tell you: Users show how big your audience is, sessions show how often people come, and views show which content is being read. For how each one is counted, and how they relate to each other, see users vs sessions vs views.

Engagement rate

Engagement rate measures the percentage of sessions that counted as engaged. A session is engaged if it does any one of three things: lasts longer than about 10 seconds, triggers a key event, or racks up two or more page or screen views.

What it tells you: Are people actually interested in your content, or are they landing and leaving immediately?

GA4 has both engagement rate and bounce rate

In the old version of Google Analytics (Universal Analytics), the headline metric was "bounce rate," and it meant a visit to a single page. GA4 keeps both metrics but redefines them against each other: bounce rate is simply the inverse of engagement rate, the share of sessions that were not engaged. Neither one appears in most reports by default; an Editor or Administrator has to add the metric to a detail report first.

Bounce rate

Bounce rate is the opposite of engagement rate. It is the percentage of sessions where the visitor left without engaging. A high bounce rate is not always a problem. If someone finds your phone number and calls you, they may "bounce" but they converted perfectly.

What it tells you: Context-dependent. High bounce on a key service page may need attention. High bounce on a contact page is fine.

Average engagement time

This is how long your site was actually in focus in someone's browser, added up and divided by the number of active users. There is a second, separate metric, average engagement time per session, which divides by sessions instead, so check which one your report is showing before you compare two numbers.

What it tells you: Are people reading or just scanning? Google publishes no target figure, so compare a page against your own other pages and against its own past months rather than against a number you read somewhere.

Conversion rate

A conversion, in everyday language, is a specific action you want visitors to take: filling in a form, making a purchase, clicking a phone number link. Google Analytics now calls these key events: you mark an event as a key event and it starts appearing as a column and a metric in your reports. In current Google terminology "conversion" means something narrower: an action used to measure and optimize Google Ads campaigns.

The conversion rate is the share of visits that result in one of those actions. GA4 splits it into two on-screen metrics: session key event rate (sessions with a key event ÷ total sessions) and user key event rate (users who performed a key event ÷ total users). Check which one you are looking at before comparing two figures.

What it tells you: Is your website actually working? This is the single most important business metric.

Traffic source / channel

This tells you how visitors found your site. These are GA4's own channel names, and they are worth using exactly: "Social" on its own is not one of them:

Channel	What it means
Organic Search	Arrived via a non-ad link in search results, including Google's AI Overviews and AI Mode
Direct	Typed your URL directly or used a saved link or bookmark
Referral	Clicked a non-ad link on another site, such as a blog or news site
Organic Social	Clicked a non-ad link on a social site
Paid Social	Clicked an ad on a social site
Email	Clicked a link in an email
Paid Search	Clicked an ad on a search engine: Google, Bing, Baidu and so on
AI Assistant	Arrived from a tool like ChatGPT, Gemini, Copilot or Grok

There are more channels than this in the full list, and the default ones cannot be edited, though you can build your own custom channel groups alongside them.

New vs returning users

New users: visiting your site for the first time (on that device/browser)
Returning users: have visited before

What it tells you: How many people are discovering you vs. how many loyal visitors you have.

Easy to miss

These numbers are estimates, not exact counts. Privacy settings, ad blockers, and browser restrictions mean some visits are not captured at all. Treat all analytics data as directional. Use it for trends and comparisons, not as a census.

Common questions

Which metric should I focus on most?

Start with conversions and traffic trends. Is traffic growing? Are conversions happening? Everything else helps explain why those numbers look the way they do.

What is a good engagement rate?

Google does not publish a benchmark, and any figure quoted online is somebody's private sample rather than an official target, so we will not give you one either. Compare your own months against each other instead: a rate that is climbing tells you more than any single number. If it looks low, the useful next question is whether it is low everywhere or only on certain channels, sources or pages.

Why do my numbers sometimes go down even when nothing changed?

Seasonal patterns, algorithm changes, and external news events can all affect traffic. Always compare year-over-year, not just month-over-month, to spot true trends.

Learn more

Analytics dimensions and metrics (Google Help)support.google.com