Setting Up Conversion Tracking in Google Ads

How tracking works

Google's page about conversion measurement puts it simply: "You choose what you identify as valuable, like a purchase, sign-up, or phone call". Our Google Ads basics guide lists the sources a conversion can come from. This guide covers the setup for website conversions.

Google's article on how Google Ads tracks website conversions explains the mechanism. When someone clicks an ad, Google Ads stores cookies with "a unique identifier for a user or the ad click that brought the user to your site." When that person converts, "the conversion tracking tag you installed reads this cookie and sends it back to Google Ads with the conversion information." For this to work, Google asks you to:

• "Turn on auto-tagging in all your Google Ads accounts."
• make sure any click trackers or server-side redirects pass on the GCLID (Google click identifier) to your landing pages;
• use the domain linker if the conversion page is on a different domain from the landing page;
• avoid firing tags inside an iframe.

The GCLID matters again later if you import sales from a CRM; that process is in our guide to offline conversion import.

Conversion actions and how to create them

A conversion action is one thing you want counted, such as a sent contact form or a purchase. Google's set up your web conversions article starts in the Goals menu: Summary, then "+ Create conversion action", then enter your domain and scan it. The scan looks for an existing Google tag or Google Analytics property. If none is found, you can set up a tag at the end.

Google describes two setup methods:

• Set up with URL: "Best for simple tracking of page loads", such as a thank-you page.
• Set up with code: "Required for tracking button clicks, dynamic values, like variable purchase amounts, or transaction IDs."

Each action gets a category, such as a purchase or a submitted lead form. Google says: "The category should be the most closely related to the user action you are measuring." It also warns that CMS plugins may add their own tags, so "ensure that you’re not double-tagging your site, which can cause duplicate conversion reporting."

If you already use Google Analytics, you can import events instead. Google says "Only events marked as key events in Google Analytics are eligible for import", that you need Admin access in Google Ads and Edit access in the property, and that after linking "it can take 24 to 48 hours" before the import options appear. Our GA4 basics guide explains key events.

The Google tag and event snippet

Google's page about the Google tag says it is "a single tag you can add to your website that allows you to use a variety of Google products and services." The older global site tag is now the Google tag: "If you have a global site tag on your website, you don’t need to update your site to use the Google tag."

For Google Ads, the Google tag article for conversion tracking explains that the tag "works in unison with another piece of code, an event snippet or a phone snippet". The event snippet "tells the Google tag when to track a conversion" and "should be installed on the conversion page itself", after the Google tag. Google adds: "Ensure the correct conversion ID and label are used".

You can also deploy both through Google Tag Manager. In that case Google's tracking article asks for a Conversion Linker tag set to fire on all pages; it "automatically detects the information about the ad click that brought someone to your site in the landing page URLs and stores this information in new cookies on your domain." Containers, triggers and publishing are covered in our Google Tag Manager basics guide. Pick one method; the Google tag article advises checking for conflicts if you use gtag.js and Tag Manager at the same time.

Consent applies to all of this. Google asks advertisers to "get consent where required by law or any applicable Google policies governing user consent, including Google’s EU user consent policy." Our cookie consent guide explains how banners and consent settings fit in.

Counting, windows and values

Three settings on each action change what the numbers mean.

Counting. Google's page about conversion counting options offers two choices. "Every conversion" counts each conversion after an ad interaction, which suits sales. "One conversion" counts "only one conversion per ad click", which suits leads, because "usually only one, unique lead per ad click likely adds value for your business." A shop might count every purchase but only one quote request per click.

Conversion window. Google defines it as "the period of time after an ad interaction (such as an ad click or video view) during which a conversion, such as a purchase, is recorded in Google Ads." Its page about conversion windows says the default click-through window is 30 days, and that changes "apply to all conversions going forward". It suggests the time lag report to see how long your customers take. If your buyers often take weeks to decide, check this setting early.

Values. Google's page about conversion values says values let you see "the total business value that Google Ads generated, rather than simply the number of conversions". You can use the same value for every conversion, or different values for each one. For different values, "you'll need to add dynamic values to your tracking code", otherwise "the default value you enter will be used for all conversions." Values are what Target ROAS and Maximize conversion value bid strategies work from.

Goals, primary and secondary actions

Google groups conversion actions into goals. Its article on primary and secondary conversion actions explains the split:

• Primary actions are "reported in the “Conversions” column in your reports and used for bidding" when their goal is used for bidding.
• Secondary actions "are for observation only". They appear in "All conversions" but are not used for bidding, unless they are part of a custom goal.

Google calls getting this right "critical", because misconfigured settings "can prevent Smart Bidding from optimizing effectively". Conversions created from Google Analytics "are secondary by default" and can only be changed to primary in Google Ads.

Goals can be account-default or campaign-specific. Google's page about conversion goals recommends that if several standard goals track stages of the same funnel, you "set only one of them as the account-default goal". A practical reading: make the action that means real business primary, such as a submitted enquiry or a purchase, and keep softer signals such as page scrolls or brochure downloads secondary.

Enhanced conversions

Cookies are not always available, so Google offers enhanced conversions. Google says the feature "supplements your existing conversion by sending hashed first party conversion data", such as an email address, and uses "a secure one-way hashing algorithm called SHA256" before sending it. There are two types:

• Enhanced conversions for web, for "sales and events that happen on a website";
• Enhanced conversions for leads, for sales "that happen off a website" from website leads. That type works with imported offline conversions, covered in our offline import guide.

Google's setup article for the Google tag covers how to turn it on. Because it uses customer data, check it against your privacy notice and consent setup before you switch it on.

Attribution models

A customer may click several of your ads before converting. Attribution decides which click gets the credit. Google's page about attribution models now lists two models:

• Last click: "Gives all credit for the conversion to the last-clicked ad and corresponding keyword."
• Data-driven: "Distributes credit for the conversion based on your past data for this conversion action." Google says it "is the default attribution model for most conversion actions."

Google states that "The first click, linear, time decay, and position-based attribution models are no longer supported", and that actions which used them "have been upgraded to use data-driven attribution." The model you pick is set per action and affects bid strategies that use the Conversions column, such as Target CPA and Target ROAS. Google recommends testing a new non-last-click model first and assessing how it affects your return on investment.

Checking it works

Google's setup article says to check the "Status" column for each action in the Goals summary. Its page about conversion measurement notes that an Unverified or Inactive status "is normal for new tags." The status changes to Active after the first conversion or a successful test. Google suggests Tag Assistant to check the tag. After launch, complete a conversion yourself on the live site and check that the status updates. Use UTM links for other channels, so Google Analytics can show the wider picture alongside Google Ads.

A checklist

• Auto-tagging on; redirects and click trackers keep the GCLID.
• One Google tag on every page, deployed one way only (code or Tag Manager).
• One conversion action per real business result, with the right category.
• Counting set to one conversion for leads and every conversion for sales.
• A conversion window that fits how long your customers take.
• Values set, dynamic where amounts vary.
• Only the actions that matter marked primary.
• Enhanced conversions reviewed against your privacy notice and consent.
• Attribution model chosen on purpose, and the status column checked after a test.

FAQ

Do I need Google Tag Manager to track Google Ads conversions?

No. You can add the Google tag and event snippet to the site directly, or deploy them through Google Tag Manager with a Conversion Linker tag on all pages. Google advises checking for conflicts if both methods run at the same time.

Should I count every conversion or one conversion?

Google suggests every conversion for sales, because each sale adds value, and one conversion for leads, because usually only one unique lead per ad click adds value. You can choose differently for each conversion action.

What is the difference between primary and secondary conversion actions?

Primary actions appear in the Conversions column and are used for bidding when their goal is used for bidding. Secondary actions are for observation only and appear in All conversions, unless they are part of a custom goal.

Which attribution models can I use in Google Ads?

Google Ads Help now lists last click and data-driven. Google says first click, linear, time decay and position-based are no longer supported, and actions that used them were upgraded to data-driven attribution.

Why does my new conversion action show Unverified?

Google says an Unverified or Inactive status is normal for new tags. It changes to Active after Google Ads records its first conversion or a successful test event. Google suggests Tag Assistant to check the setup.

Want your website forms and Google Ads connected so you can see which ads bring in customers? See our website development service and all our services, or email [email protected].