Google Analytics GA4 Setup: Sign Up, Install, Find Measurement ID

Google Analytics (GA4) is an analytics tool you set up in this order: account, property, data stream. Then you add a tag with the stream's measurement ID to your site and confirm collection in the Realtime report. As of October 3, 2026, Google says new properties can take up to 30 minutes to show data. This guide helps site owners and ad managers who are installing it for the first time follow each step, from sign-up to install check.

Know the structure before you sign up: account, property, data stream

Google Analytics has three levels: account, property, and data stream. The account is the largest unit and holds a company or brand. A property is one analysis unit for a site or app inside it. A data stream is the channel that brings in data from a website or app. One account can hold up to 2,000 properties.

You copy the measurement ID for the tag from the data stream details. So you cannot skip the account and property and install the tag first. The product called Google Analytics today is GA4. The previous generation, Universal Analytics standard properties, stopped processing data on July 1, 2023.

How to create a GA4 account, property, and data stream

Sign in to analytics.google.com with your Google account and follow the steps below. Creating an account requires Editor access or higher at the account level. Creating a property and a data stream each require Editor access. If you are joining an account made by an agency, check your own Google account's role first.

1. Click "Start measuring," name the account, and choose your data sharing settings.
2. Enter the property name, reporting time zone, and currency. For a Korean site, we recommend Seoul as the time zone and Korean won as the currency.
3. Choose your industry, business size, and usage goals. Google says it sets up your reports automatically based on your goals.
4. For a website, choose "Web" under data streams, then enter the site URL and a stream name.
5. On the stream details screen, copy the measurement ID that starts with G-. To find it again later, go to Admin > Data streams and click the stream name. The measurement ID appears in the stream details.

It is better to set the time zone when you first create the property. The official documentation warns that changing the time zone more than twice a day can delay report processing and make data look odd.

How to install Google Analytics: 4 ways to add the tag to your site

The tag is a short piece of code that sends visit information to Google Analytics. Google calls it the Google tag. Pick one of the options below based on your site setup.

Install method	Use it when	What you do
Enter in a CMS or website builder	Your platform has a Google Analytics input field	Paste the measurement ID or Google tag ID into the field. You do not edit code.
Paste into the CMS custom code field	There is no input field, but you can add header code	Paste the whole code block from the direct install below into that field.
Insert directly into the page	You have permission to edit the HTML	Paste the code right after the <head> element on each page.
Google Tag Manager	You already manage site tags with a tag manager	Add a Google tag in the tag manager and enter the measurement ID.

The code for direct insertion is the whole block that starts with the <!-- Google tag (gtag.js) --> comment and ends with </script>. Pasting only part of it will not work. If you use direct insertion and a tag manager on the same site, the same tag can fire twice and count visits double. We recommend sticking to one method. If you choose the tag manager route, start with GTM basics: manage tags without editing code using Google Tag Manager.

Check your Google Analytics install: find your own visit in the Realtime report

The official documentation says to confirm data collection with the Realtime report. After adding the tag, open your site in an incognito window or another browser. If the Realtime report in the Google Analytics Reports menu shows at least 1 user, collection has started. New properties can take up to 30 minutes to show data. Do not assume the install is wrong just because nothing appears in the first few minutes.

If nothing shows after 30 minutes, check in order whether the tag sits after the head element on every page, and whether the measurement ID in the code matches the value on the stream screen. Key pages such as the order confirmation page or the contact page are easy to miss, so we recommend opening at least three main pages yourself to check.

First GA4 settings: enhanced measurement and data retention

Enhanced measurement is a stream setting that automatically collects page views, scrolls, outbound link clicks, site search, video engagement, file downloads, and form interactions without extra code. According to the official documentation, the scroll event fires when a user reaches 90% of the page height, and page views cannot be turned off. To find the setting, go to Admin > Data collection and modification > Data streams, open the stream, and use the enhanced measurement switch. The settings icon lets you turn each item on or off.

The same document warns you to take care not to collect personally identifiable information. If search terms or form values on your site can include names or emails, review those items before turning them on.

You set data retention under Admin > Data settings > Data retention. Standard properties let you choose between 2 months or 14 months. According to the same document, extending retention also applies to data you already collected. A change is confirmed after a 24-hour grace period, and you can reverse it within that time with no data loss. Demographic data such as age, gender, and interests is kept for only 2 months, regardless of this setting.

Common mistakes when starting with Google Analytics

Installing the tag twice. This happens when you add the same measurement ID in a tag manager while directly inserted code is still on the page. Pick one install method and remove the other.

Entering a value that differs from the stream's measurement ID. The Google tag ID is a different value from the measurement ID. To check that the ID in the tag code matches the measurement ID on the stream screen, compare it in the stream details.

Installing once and never opening the main pages. If data shows up only on the home page and the checkout and contact pages are missing, your most important actions go unmeasured. Right after installing, check page by page in the Realtime report.

Fixing the time zone and currency later. A changed value does not rewrite earlier data, so daily numbers can fall out of line. Set Seoul and Korean won when you first create the property.

Frequently asked questions

Are the GA4 measurement ID and the Google tag ID the same value?

No, they differ. The measurement ID starts with G- and points to a data stream. The Google tag is the code you place on your website.

How is Google Analytics 4 different from the old Universal Analytics?

GA4 is a new kind of property that collects web and app data together using an event-based model rather than a session-based one. Universal Analytics standard properties stopped processing data on July 1, 2023, so use GA4 if you are starting fresh.

Can I see website and app data in one place?

GA4 is designed to collect website and app data together. On the app side, you connect it by installing the Firebase SDK in the app rather than using the web tag.

What to do today

Create an account and property at analytics.google.com, and set the time zone to Seoul and the currency to Korean won. Copy the measurement ID from the web data stream and add the tag using the one install method that fits your site. Then open the site in an incognito window and check that your visit shows up in the Realtime report. Once data starts to build up, open the 5 reports to check first. To separate visits that come from ads or newsletters, read the UTM parameters article first.