A Beginner's Guide to Using a Tracking ID: From Basic Operations to Advanced Tips

Are you struggling with questions like "Where do I check the tracking ID?" or "I don't know how to install it"? The tracking ID is an essential identifier for correctly measuring website data in access analysis tools such as Google Analytics. This article explains everything from the basic meaning of the tracking ID to how to check, issue, and install it, as well as advanced topics such as linking with GTM and avoiding duplicate measurement, in a way that is easy for beginners to understand.

What Is a Tracking ID?

A tracking ID is a unique ID used by an access analysis tool to identify "which website's data" it is dealing with. A unique number is assigned to each site (more precisely, to each property), and based on this ID, data such as the number of visitors and page viewing activity is collected and classified.

The most representative example is the Google Analytics tracking ID. The tracking ID refers to a string contained within the "tracking code," which is the source code used for measurement. Only by installing this code on your website does access analysis become possible.

The Difference Between a Tracking ID and a Measurement ID

Google Analytics has different versions, and the way the ID is referred to differs for each. Let's go over the difference between the currently mainstream GA4 (Google Analytics 4) and its predecessor, UA (Universal Analytics).

• Tracking ID (UA): The ID used in Universal Analytics, the older version. It has the format "UA-XXXXXXXX-X," and support for UA ended in July 2023.
• Measurement ID (GA4): The new ID used in the current GA4. It has the format of an alphanumeric string starting with "G-" (for example, G-ABC12DE3F).

Originally, "tracking ID" was the term used in the UA era, but now that the migration from UA to GA4 is complete, it has become common to broadly call the GA4 "measurement ID" a "tracking ID" as well. When you start with Google Analytics from now on, a GA4 property will be created, so what you actually handle will be the measurement ID starting with "G-."

How to Check Your Tracking ID (Measurement ID)

If you have already created a GA4 property, you can check the measurement ID from the admin screen. Follow the steps below.

1. Log in to GA4 and click the gear icon "Admin" at the bottom left of the screen.
2. Select "Data Streams" in the "Property" column.
3. Click the data stream you want to measure.
4. The measurement ID starting with "G-" is displayed at the top right of the screen that appears.

The string starting with "G-" displayed here is the tracking ID (measurement ID) in GA4. Since you will use this ID when linking with GTM or installing the code, copy it and keep it on hand.

Steps to Issue a Tracking Code

If you do not yet have a GA4 property, you first need to create an account and a property. When you create a property, a measurement ID and a tracking code are issued automatically.

1. From the "Admin" screen in GA4, select "Create property" and set the property name, time zone, and other details.
2. Create a website data stream as the measurement target, and enter the site URL and stream name.
3. After creation is complete, the measurement ID and Google tag (tracking code) are issued.

How to Install the Tracking Code on Your Website

By installing the issued tracking code on your website, measurement begins. There are mainly two installation methods.

Method 1: Install Directly in the HTML

The simplest method is to paste the code into the HTML. Open the HTML file of the page you want to measure, and paste the tracking code immediately after the opening of the head tag. In the UA era, placement just before the closing of the head tag was recommended, but in GA4, placement as high as possible within the head tag is recommended.

Method 2: Install with Google Tag Manager (GTM)

If you want to manage multiple tags together, using Google Tag Manager (GTM) is recommended. With GTM, once you edit the HTML the first time, you can add and edit tags from the GTM admin screen afterward, reducing the effort of editing the HTML directly.

The basic flow for installation with GTM is to choose "Google Analytics: GA4 Configuration" in a GTM tag, enter the measurement ID you checked earlier (the ID starting with G-), specify "All Pages" as the trigger, and publish.

Check Whether Measurement Is Working Correctly

Once installation is finished, be sure to confirm that data is being collected correctly. A handy method is to open the "Realtime" report in GA4, access the site yourself, and see whether your visit is reflected. If it is not reflected, check whether the measurement ID is entered correctly and whether the tag is firing in GTM. Since data may not yet be collected immediately after linking, it is a good idea to wait a little and then check.

Points to Note When Using a Tracking ID

To obtain accurate data, you need to pay attention to the following points during installation.

Beware of Duplicate Measurement

Duplicate measurement is a mistake in which the same tracking code is installed multiple times on a single page. For example, it occurs when you write the code directly in the HTML and also set up the same measurement with GTM or a WordPress plugin. When duplicate measurement occurs, page views become double the actual figure or the bounce rate drops to an extreme, harming the accuracy of the data. If the bounce rate is unnaturally low, such as below 20%, suspect duplicate measurement and check the installation status. The remedy is to keep only one measurement method and remove the others.

Check Your CMS Compatibility

Many CMSs such as WordPress and Wix support GA4, but some do not support the measurement ID starting with "G-." Since installing a measurement ID on an unsupported CMS will not measure any data, check the compatibility status in advance.

Summary

A tracking ID is a unique ID that an access analysis tool uses to identify which website's data it is. In Google Analytics, the ID migrated from the old UA tracking ID starting with "UA-" to the current GA4 measurement ID starting with "G-." You can check the measurement ID from the data stream in the admin screen, and you install it on your website either directly in the HTML or via GTM. After installation, confirm measurement with the Realtime report, and by paying attention to duplicate measurement and CMS compatibility, you will have a solid foundation for accurate data measurement. Start by checking your own site's measurement ID.