One of the biggest blockers for Google Tag Manager\u2019s<\/a> server-side tagging<\/a> to slip out of beta<\/em> is Google Ads<\/strong>. Until server-side tagging supports a solution for both conversions<\/strong> and remarketing<\/strong> capabilities to be reproduced server-side, it\u2019s unlikely that Server containers will lose their beta label.<\/p>\n <\/p>\n <\/a><\/p>\n<\/div>\n While I can\u2019t say what will happen to the beta label now, the fact is that Google Tag Manager has now released support for Conversion tracking<\/strong> using server-side tagging.<\/p>\n The whole thing is quite \u2026 interesting, as it involves not just server-to-vendor<\/strong> calls, but also browser-to-server-to-browser-to-vendor<\/strong> requests. Why? Maybe you guessed it: third-party cookies<\/em>.<\/p>\n In this article, I\u2019ll show you how to set things up (surprisingly simple), and I\u2019ll also try to shed some light on how the whole setup actually works (surprisingly difficult).<\/p>\n Here is the official documentation on Google Ads and Server-side Tagging: Google Ads conversions (Google)<\/a>.<\/p>\n \n \n Subscribe to the Simmer newsletter<\/a> to get the latest news and content from Simo Ahava into your email inbox!\n <\/p>\n <\/span><\/p>\n In the web container<\/strong>, you need to reconfigure the Google Analytics 4<\/strong> Config tag to send the data to the Server container using the new Send to server container<\/strong> option. This replaces the Note!<\/strong> Server-side tagging with Google Ads only works with Google Analytics 4<\/em>. It will not<\/strong> work with Universal Analytics tags.<\/p>\n<\/blockquote>\n The point here is that you\u2019ll use your GA4 web tag(s) to send the conversion events to the Server container, where they will then be mapped accordingly.<\/p>\n In the Server<\/strong> container, you\u2019ll need these two tags:<\/p>\n Both of these are new, built-in tag templates in all Server containers.<\/p>\n Let\u2019s start from the top.<\/p>\n For the Google Ads setup to work, you\u2019ll need to update the Google Analytics: GA4 Configuration<\/strong> tag to use the new Send to server container<\/strong> setting, and you\u2019ll need to remove<\/strong> the <\/p>\n <\/a><\/p>\n<\/div>\n You need to populate the Send to server container<\/strong> setting with the exact same value you populated When you set the new Send to server container<\/strong> setting, it does two things.<\/p>\n The second is quite important in this scenario. The purpose of the field is to tell GA4 (in the web) that the target machine is not<\/strong> a computer owned by Google Analytics. This means that it enables the protocol to share potentially sensitive data, as the Server container is something owned by the company running the website (hopefully) and not Google Analytics.<\/p>\n When <\/p>\n <\/a><\/p>\n<\/div>\n This protocol is essentially a response message, which is then parsed by the GA4 web tags, and they will react accordingly (e.g. send the request to the DoubleClick domain<\/strong> as in the example above).<\/p>\n We\u2019ll return to this topic, but suffice to say this is done because Conversion Tracking still makes use of third-party cookies<\/strong><\/em>.<\/p>\n In the Server container<\/strong>, create a new Conversion Linker tag. You\u2019ll find it in the list of built-in tag templates.<\/p>\n <\/p>\n <\/a><\/p>\n<\/div>\n There\u2019s a new built-in trigger called All Pages<\/strong> in the Server container. Add that to the tag, as you\u2019ll want the Conversion Linker to activate on all pages.<\/p>\n The All Pages<\/strong> trigger fires whenever there\u2019s an event named The Conversion Linker tag does two things.<\/p>\n <\/p>\n <\/a><\/p>\n The landing page beacon sent to Google Ads servers<\/span><\/p>\n<\/div>\n The landing page beacon is very non-descript. It\u2019s just a ping to Google Ads with the current URL. Naturally, the URL might contain the <\/p>\n <\/a><\/p>\n The FPGCLAW cookie written with a 3-month expiration<\/span><\/p>\n<\/div>\n The Next, you can go ahead and create a Google Ads Conversion Tracking<\/strong> tag in the server. You configure it exactly as you would configure the same tag in a web container.<\/p>\n <\/p>\n <\/a><\/p>\n<\/div>\n Set it to fire on whatever trigger you want to use for this particular conversion. In the example above, I\u2019m using an This is where things get interesting.<\/p>\n If there\u2019s a first-party click ID available, such as the one stored in <\/p>\n <\/a><\/p>\n<\/div>\n This is a \u201cnormal\u201d Google Ads Conversion request. It contains the conversion ID, the conversion label, and the Click ID in the But when you then look at the response<\/em> back from the Google server, you\u2019ll see it\u2019s a 302 redirect to the DoubleClick domain.<\/p>\n <\/p>\n <\/a><\/p>\n<\/div>\n Why? Because the Google Ads Conversion tag needs to communicate with the DoubleClick domain to stitch the conversion information with the user\u2019s identity, and this requires DoubleClick to read its cookies in third-party context.<\/p>\n However<\/strong>, since the Server container can\u2019t work with third-party cookies, things get complicated.<\/p>\n What happens is that the HTTP response<\/strong> back from the Server (i.e. for the <\/p>\n <\/a><\/p>\n<\/div>\n And sure enough, if you look at the network requests (in a browser that supports third-party cookies), you\u2019ll see the browser requests to Google servers:<\/p>\n <\/p>\n <\/a><\/p>\n<\/div>\n In case the browser doesn\u2019t<\/strong> have first-party click ID information stored, the Server container doesn\u2019t<\/strong> send a direct request to Google servers. Instead, it just instructs the browser to send the requests, so that the third-party cookies can be picked up.<\/p>\n Please don\u2019t ask me what happens if the browser doesn\u2019t support third-party cookies. My guess is that if the Click ID is present, your conversion measurement will work just fine. However, there might be limitations on what type of audiences you can use or build for conversion tracking, because the click and the conversion can\u2019t be attributed to a generic Google user without third-party cookies.<\/p>\n Similarly, if the first-party Click ID is not<\/em> available, I\u2019m guessing Google uses third-party cookies to see if the user has interacted with the ad nevertheless. So you\u2019ll lose that fallback if third-party cookies are not supported.<\/p>\n What about Consent Mode<\/a>? What happens if First, the Conversion Linker<\/strong> tag sends the landing beacon<\/em> ping to Google servers, but it doesn\u2019t write the The landing page beacon includes parameters which state that Consent Mode is active. These instruct Google to ignore any identifiers in the request and only collect anonymous data for conversion modeling.<\/p>\n <\/p>\n <\/a><\/p>\n<\/div>\n The Conversion Tracking tag<\/strong> sends the server-to-server request normally, whether a first-party click identifier is available or not:<\/p>\n <\/p>\n <\/a><\/p>\n<\/div>\n If the page URL has the <\/p>\n <\/a><\/p>\n<\/div>\n If, however, consent changes<\/em> to granted<\/strong>, the GA4 web tag reacts.<\/p>\n The This means that the Conversion Linker (assuming it fired on All Pages) will fire again and this time rewrite the In addition to this, any other event you have marked as a conversion<\/a> in the Google Analytics 4 user interface<\/strong> will also<\/em> get sent again.<\/p>\n In other words, if you want your <\/p>\n <\/a><\/p>\n<\/div>\n The GA4 UI will instruct the Note! Even though the hits are sent again, the Server container will prevent tags from triggering again unless they support By the way, this applies to Finally, there\u2019s a new Custom Template<\/a> API: The GA4 web tag then picks up this instruction and sends the request via the browser.<\/p>\n This means that other vendors that require third-party cookies to run can utilize this API to engineer their templates to use the browser rather than direct server-to-server hits.<\/p>\n Note! This only<\/em> works with a GA4 web tag. If the request originates from some other dispatch source, the API will not work as intended.<\/p>\n<\/blockquote>\n As you can see, setting up Google Ads tracking is quite simple. But understanding the flow<\/em> is another thing indeed.<\/p>\n I\u2019m actually somewhat disappointed at how the setup works. I\u2019m not saying I don\u2019t think it\u2019s a good piece of software \u2013\u00a0it is! I just dislike the fact that it relies on third-party cookies.<\/p>\n Forcing the browser to do all the legwork means that some of the most important security benefits of server-side tagging (reliance on first-party connections only, stricter Content-Security Policies) need to be abandoned in favor of getting more data.<\/p>\n I\u2019m wondering why Google isn\u2019t pushing more aggressively for a first-party-only approach such as Enhanced Conversions<\/a>. I\u2019m not really a big fan of this, either, but at least the website and server-side tagging setup would retain control, rather than having it relinquished to third-party requests that originate in the browser.<\/p>\n![\"google-ads-server-side-tagging-google-tag-manager.jpg\"\/](\"https:\/\/www.simoahava.com\/images\/2021\/07\/google-ads-server-side-tagging-google-tag-manager.jpg#ZgotmplZ\")
<\/p>\n
\n X<\/span><\/p>\n
\n The Simmer Newsletter<\/strong>\n <\/p>\nThe components you\u2019ll need<\/h2>\n
transport_url<\/code> setting you\u2019ll have used until now.<\/p>\n\n
\n
Web: Update the GA4 Config tag<\/h2>\n
transport_url<\/code> field.<\/p>\n![\"Send](\"https:\/\/www.simoahava.com\/images\/2021\/06\/send-to-server-container.jpg#ZgotmplZ\")
<\/p>\ntransport_url<\/code> with: the origin<\/em> of the Server container, i.e. the URL up to the path selector. See the image above for an example.<\/p>\nHow it works<\/h3>\n
\n
transport_url<\/code> to point to the Server container.<\/li>\nfirst_party_collection<\/code> field to true<\/code>.<\/li>\n<\/ol>\nfirst_party_collection<\/code> is enabled, GA4 will use a new protocol that allows the Server container to communicate back<\/em> to the browser.<\/p>\n![\"Response](\"https:\/\/www.simoahava.com\/images\/2021\/07\/server-conversion-response.jpg#ZgotmplZ\")
<\/p>\nServer: Create a Conversion Linker tag<\/h2>\n
![\"Conversion](\"https:\/\/www.simoahava.com\/images\/2021\/06\/conversion-linker.jpg#ZgotmplZ\")
<\/p>\npage_view<\/code> generated by a Server container Client.<\/p>\nHow it works<\/h3>\n
\n
gclid<\/code> parameter, or if there are Google Ads\u2019 first-party cookies in the request, the tag will set the new FPGCLAW<\/code> cookie in the response, writing the click ID to storage.<\/li>\n<\/ol>\n![\"The](\"https:\/\/www.simoahava.com\/images\/2021\/06\/landing-page-beacon.jpg#ZgotmplZ\"){kind=tracking}
<\/p>\ngclid<\/code> parameter, so I\u2019m guessing this is used to validate clicks on ads.<\/p>\n![\"The](\"https:\/\/www.simoahava.com\/images\/2021\/06\/fpgclaw-cookie.jpg#ZgotmplZ\")
<\/p>\nFPGCLAW<\/code> cookie seems to just replicate the pre-existing Google Ads cookies in that it writes the Google Ads Click ID into a first-party cookie. Naturally, as it\u2019s done in a Set-Cookie<\/code> server response, it\u2019s better warded against tracking protections<\/a>.<\/p>\nServer: Create a Google Ads Conversion Tracking tag<\/h2>\n
![\"Google](\"https:\/\/www.simoahava.com\/images\/2021\/06\/google-ads-conversion-tag.jpg#ZgotmplZ\")
<\/p>\nadd_to_cart<\/code> event generated by the GA4 Client.<\/p>\nHow it works<\/h3>\n
FPGCLAW<\/code> by the Conversion Linker tag, the Server container sends the conversion event directly to Google Ads servers.<\/p>\n![\"Google](\"https:\/\/www.simoahava.com\/images\/2021\/06\/google-ads-conversion.jpg#ZgotmplZ\")
<\/p>\ngclaw<\/code> parameter, among other things.<\/p>\n![\"Conversion](\"https:\/\/www.simoahava.com\/images\/2021\/06\/conversion-doubleclick.jpg#ZgotmplZ\")
<\/p>\nadd_to_cart<\/code> event) contains a message that instructs the GA4 library in the browser<\/strong> to compose the DoubleClick request instead.<\/p>\n![\"Server](\"https:\/\/www.simoahava.com\/images\/2021\/06\/server-response-add-to-cart.jpg#ZgotmplZ\")
<\/p>\n![\"Google](\"https:\/\/www.simoahava.com\/images\/2021\/06\/google-server-requests.jpg#ZgotmplZ\")
<\/p>\nInteraction with Consent Mode<\/h2>\n
ad_storage<\/code> is denied? Or what if it\u2019s subsequently granted?<\/p>\nIf consent is denied<\/h3>\n
FPGCLAW<\/code> cookie<\/em> in the HTTP response.<\/p>\n![\"Consent](\"https:\/\/www.simoahava.com\/images\/2021\/06\/consent-mode-linker-ping.jpg#ZgotmplZ\")
<\/p>\n![\"Conversion](\"https:\/\/www.simoahava.com\/images\/2021\/06\/conversion-consent-mode.jpg#ZgotmplZ\")
<\/p>\ngclid<\/code> parameter, then that is sent to Google Ads (as in this scenario no Ads cookies are needed).<\/p>\n![\"Conversion](\"https:\/\/www.simoahava.com\/images\/2021\/06\/conversion-ping-with-click-id-consent.jpg#ZgotmplZ\")
<\/p>\nIf consent changes to granted<\/h3>\n
page_view<\/code> hit is immediately resent to the Server container. This time it doesn\u2019t have the consent restrictions in place, so both GA4 tags and Google Ads tags will be able to benefit from the regular, cookies-enabled ping.<\/p>\nFPGCLAW<\/code> cookie.<\/p>\nadd_to_cart<\/code> Google Ads conversion event to be sent with cookies and full capabilities as soon as consent is granted, you need to go into the Google Analytics 4 UI and mark the add_to_cart<\/code> event as a conversion.<\/p>\n![\"add_to_cart](\"https:\/\/www.simoahava.com\/images\/2021\/06\/add_to_cart-conversion.jpg#ZgotmplZ\")
<\/p>\ngtag.js<\/code> library to account for the add_to_cart<\/code> conversion event when sending the hits again after consent is granted. You need to do this for all<\/strong> events that you want the library to send again once consent is granted!<\/p>\n\n
ad_storage<\/code>.<\/p>\n<\/blockquote>\nanalytics_storage<\/code> as well (of course nothing is sent to Ads in this case). When analytics_storage<\/code> is set to 'granted'<\/code>, GA4 collects the page_view<\/code> and all previously sent, cookieless conversion events again automatically.<\/p>\nNew API<\/h2>\n
sendPixelFromBrowser<\/code>. This API works together with a GA4 web tag. If the API is invoked and the request originated from a GA4 web tag, the API sends the pixel request back to the browser using the same protocol as the Google Ads tags above.<\/p>\n\n
Summary<\/h2>\n