Google Ads Conversion Tracking: Setup, Tags and Shopify Guide

Google Ads conversion tracking is a tag on your website that tells Google Ads when a click turned into a sale, a lead or a call. Without it, Google Ads can tell you what you spent but not what you got. With it, you can see which keywords, ads and products make money, and Smart Bidding has something real to learn from.

Having a tag is the easy part. The costly mistakes are quieter: purchases counted twice, the wrong action set as the goal, or a tag that stopped firing months ago. This guide covers the setup and the checks that catch those mistakes.

What counts as a conversion

A conversion is any action you decide is valuable. Google lists the sources you can measure:

• Website conversions, like purchases, sign-ups and form fills.
• App conversions, like installs and in-app purchases.
• Phone calls, from your ads, from a number on your site, or from clicks on a number on mobile.
• Offline conversions, like sales closed in a store or on the phone, uploaded from a file or your CRM.

For an online store, the one that matters most is the purchase, with its real value. Add to cart and begin checkout are useful signals, but they are not money.

Primary and secondary conversion actions

Every conversion action is either primary or secondary. Google is blunt about why this matters: primary actions are used for bidding, secondary actions are "observation-only", and "misconfiguring these settings can prevent Smart Bidding from optimizing effectively."

The rule we use: one primary action per real business result. For a store, that is purchase. Everything else is secondary.

How Google Ads tracks conversions

When someone clicks your ad, Google adds a click ID to the landing page URL. It is called the GCLID (Google click identifier), and it is like a ticket number for that one click. A tag on your site stores it in a first-party cookie. When the person buys, the conversion tag reads the cookie and reports the sale to Google Ads.

Google's checklist for this to work:

1. Auto-tagging is on in your Google Ads account.
2. The tag runs on every page, not only the thank-you page. Google calls this a site-wide tag.
3. Redirects and click trackers keep the GCLID. If something strips it, the sale cannot be matched.
4. Cross-domain checkouts are linked. If your checkout is on a different domain, use the domain linker.
5. The tag is not inside an iFrame (a small page loaded inside another page).

When some conversions cannot be observed, for example across devices with no Google sign-in, Google says it adds modeled conversions to the Conversions column as estimates.

Google tag or Google Analytics?

When you set up a conversion, Google Ads asks where the data should come from. Google's guidance:

If you pick both, be careful. A purchase imported from Google Analytics and the same purchase from the Google tag, both set as primary, count the sale twice. Smart Bidding then thinks your ads work twice as well as they do.

To import from Google Analytics, Google says you need Admin access in Google Ads, Edit access in the Analytics property, the event marked as a key event, and the accounts linked. New links can take 24 to 48 hours before the import option shows.

How to set up conversion tracking in Google Ads, step by step

This is Google's current three-step flow.

Step 1: add your website as a data source

1. Open the Goals menu and go to Summary.
2. Select Create conversion action.
3. Select Edit data sources for "Conversions on a website".
4. Enter your domain and select Scan. Google checks for a Google tag or a Google Analytics property.

Step 2: create the conversion action

Pick a category, like Purchase. Then pick one of three ways to measure it:

A. With a URL, no code. Best for "count a visit to this page", like a thank-you page. You pick a match type: URL is, URL contains, or URL starts with. Google notes the limits: you cannot pass a different value per order, you cannot use Tag Manager for it, and you cannot set up enhanced conversions by editing event code.

B. Manually with code. Needed for button clicks, a real order value or a transaction ID. You get an event snippet to add to the page.

C. With Google Tag Manager. Covered in the next section.

Then check the settings:

• Value. For a store, pass the real order value. If every sale is worth the same, a fixed value works. Google says "don't use a value" is not recommended.
• Count. Every is best for sales. One is best for leads, where a second form fill from the same click adds nothing.
• Click-through conversion window. How long after a click a conversion still counts. Default 30 days, up to 90 depending on the source. Google recommends at least 7 days.
• Engaged-view window. For video. Default 3 days.
• View-through window. Default 1 day. More on this below.
• Attribution model. How credit is shared across clicks.

Step 3: install the tag and check it

From the next steps screen, set up the Google tag if you do not have one, and add the event snippet if you chose code. Then go back to Goals, Summary and read the Status column.

A new action shows Unverified or Inactive at first. Google says that is normal until it records the first conversion or a test event. After a fix, the status can take up to 48 hours to update.

Google Tag Manager for Google Ads

Tag Manager lets you add and change tags without editing your site code each time. For Google Ads you need two tags:

1. A Conversion Linker tag, firing on All Pages. Google says it reads the ad click details from the landing page URL and stores them in first-party cookies.
2. A Google Ads Conversion Tracking tag, firing on your purchase or lead event.

The conversion tag needs your Conversion ID and Conversion Label. Find them in Google Ads under Goals, Summary, your conversion action, Tag setup, Use Google Tag Manager. Google says the ID is unique per account and the label is unique per action. Auto-created actions do not give you a label, so create a manual one.

Add the conversion value, currency and a transaction ID as variables. Google warns that an empty value field sends 0. The transaction ID stops the same order from counting twice when someone reloads the thank-you page.

Preview in Tag Manager, place a test order, then publish.

Google Ads conversion tracking on Shopify

Shopify stores have an easier path. Google calls it the easiest way to set up conversion tracking on Shopify.

1. Install the Google & YouTube app from the Shopify App Store.
2. Connect your Google account and your Google Ads account.
3. Confirm the events. Google's help page says linking creates a purchase conversion action, set as primary and as the account default.
4. Leave the rest secondary. The app also creates add to cart, begin checkout, page view, view item, search and add payment info. Google says these are secondary, for observation only.
5. Confirm enhanced conversions when asked.
6. Remove old tags. This is the step people skip. Google tells you to remove legacy tags to avoid duplicate measurement, and to check you do not have the same conversion in the app and in your theme or a custom pixel.

Two limits from Google's help pages. The app links one Google Ads account directly, so extra accounts need manual conversion IDs and labels. And if you manage through a manager account (MCC), you may need the manual route.

For the full store setup, including Merchant Center and the first campaign, read Google Ads for Shopify.

View-through conversions, explained

A view-through conversion is when someone saw your ad, did not click it, and later converted. Google describes them as "a helpful way to track the full value of your display or video ad campaigns."

What you need to know:

• In most campaigns they stay out of the main Conversions column and are for reporting only. They sit in View-through conversions and All conversions. The exceptions are Performance Max for store goals, App and Demand Gen campaigns. Everywhere else they do not drive bidding.
• The last impression gets the credit for Display and video ads.
• They skip people who clicked any of your other ads. Those count as normal conversions.
• Browsers that block cross-site cookies cannot report them.
• The window is short by default: 1 day after the impression. A longer window records more of them.

Treat them as a hint about display and video reach, not as sales your ads definitely caused.

The Google Ads tag and the remarketing tag

People still search for "the Google Ads remarketing tag" because older guides had one tag for conversions and another for remarketing. Today the site-wide Google tag does both jobs, and Google calls the old one the "legacy remarketing tag".

The exception is dynamic remarketing, which shows people the exact products they looked at. Google says that needs a tag with custom parameters on every page, passing the IDs of the items viewed. More on audiences in our remarketing guide.

How to test that tracking works

Do these five checks after every setup and after every theme or checkout change:

1. Place a real test order and watch it arrive in Google Ads. Expect a delay.
2. Run Google Tag Assistant on your site. Google recommends it for checking tags.
3. Count your primary actions. One per real result. Two primary purchase actions means double counting.
4. Compare with your store. Over a full month, Google Ads purchases should be close to the orders your store shows from Google Ads clicks. Far more means double counting. Far fewer means lost tags.
5. Check the conversion delay. Google says conversions can be reported up to 90 days after the click, depending on your window. Recent days always look worse than they will end up. Use the Days to conversion segment with a date range that ended at least 30 days ago.

The mistakes that break tracking

• Two primary purchase actions from the app and an old theme tag.
• Counting leads with "Every", so one person who submits a form three times looks like three leads.
• No real value, so Smart Bidding treats a $10 sale and a $500 sale the same.
• A checkout on another domain with no linker, so the click ID is lost.
• Changing goals during learning. Google says Smart Bidding has a 7 to 14 day learning phase and goal changes reset it.

For how tracking fits the bigger picture of PPC measurement, see what PPC tracking is. For how bidding uses it, see what Smart Bidding is.

Check your tracking now

If you are setting up a brand new account, start with our Google Ads setup guide. Broken tracking is the first leak we look for, because every other number depends on it. Our free Google Ads audit checks for it. If you want a second opinion from your live data, Scaley Media Buyer connects read-only and can tell you which conversion actions are primary and whether purchases look double counted. It cannot change a setting. Start the free trial.

Disclosure: Christopher Krassnig, who founded Scaley, also runs ZenoX Media, a Google Ads agency.

Where these facts come from

Checked on 2026-10-08:

• About conversion measurement, Google Ads Help - conversion sources, data sources, primary and secondary actions, status notes, the learning phase.
• Set up your web conversions, Google Ads Help - the three-step setup flow, the three methods and the status check.
• Set up conversions with a URL, Google Ads Help - URL match types, value and count settings, and the limits of the URL method.
• How Google Ads tracks website conversions, Google Ads Help - auto-tagging, the GCLID, the Conversion Linker, cross-domain linking, modeled conversions and the legacy remarketing tag.
• Google Ads conversions, Tag Manager Help - the Conversion ID and Label, the empty value note and transaction IDs.
• About conversion windows, Google Ads Help - the default windows and ranges.
• About view-through conversions, Google Ads Help - the definition and how they are reported.
• Find out how long it takes for your customers to convert, Google Ads Help - the conversion delay and the Days to conversion segment.
• Set up conversion tracking with the Google & YouTube app on Shopify, Merchant Center Help, Understand the conversion actions tracked in Google Ads and Install and migrate your tags with the Google & YouTube app - the Shopify setup, the default actions and the duplicate tag warning.
• About dynamic remarketing, Google Ads Help - the dynamic remarketing tag.