(Last updated June 2014) This post is an attempt at a whole new level of interaction. These words will transcend the barriers of time and space, bridging together the physical world and its digital counterpart. You see, in an undisclosed number of hours after the publishing of this blog post, I will be talking at the MeasureCamp<\/a> unconference on this very subject. Or, I hope I will. The whole unconference thing is somewhat confusing, and it involves lighting-fast reflexes and street smarts for slot selection; traits which I sadly lack.<\/p>\n <\/p>\n <\/a><\/p>\n<\/div>\n However, if you DO see me speak at MeasureCamp, this post is meant as a companion to that talk. And if you do not (or did not, this transcendental approach is really confusing), perhaps this post will inspire you with some ideas for your own day-to-day Google Tag Manager<\/a> use.<\/p>\n In this post, my fair friends, I\u2019ve outlined a number of cool ways in which you can use macros to make your data collection woes a thing of the past. If you don\u2019t know what macros are or how they operate, be sure to check my macro guide<\/a>. Almost all of my Google Tag Manager posts in this blog revolve around macros in one way or another, so while you\u2019re at it, check out some of my other GTM articles<\/a> as well. And sorry for this shameless self-promotion, I can\u2019t help it.<\/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 <\/p>\n <\/a><\/p>\n<\/div>\n So what is Macro Magic? Well, to put it simply, it\u2019s what follows when you accept that macros, not tags, are what make GTM the time- and effort-saver that it is. Sometimes macros make your tag setups a lot sleeker and leaner, since the flexibility that they introduce to tags greatly reduces the need to capture every single variation of tracking in its own, unique tag. Sometimes they open doors to data collection methods you didn\u2019t think were possible with traditional, on-page tracking. And sometimes they\u2019re just little helper functions, which make operating GTM so much easier.<\/p>\n The examples below fall into these categories nicely, and I\u2019m sure there\u2019s something for everyone.<\/p>\n By the way, I am really, really<\/strong> looking forward to a Google Tag Manager which is accompanied by a resource library similar to Google Analytics\u2019 solution gallery<\/a>. Just imagine how cool it would be to have a library of tags and macros you can just download and insert into your container? Well, as long as it\u2019s just a utopian dream of mine, posts like this will probably be in demand.<\/p>\n Note that not all of these are my own inventions. It would be ridiculous to claim intellectual property for some of the macros, but where prudent, I\u2019ve added a link to the source of the macro. If you feel like I\u2019ve stolen your ideas, please let me know and I\u2019ll see if I can pass credit where it is due.<\/p>\n Macro Type<\/strong>: Custom JavaScript<\/a> Instructions and description<\/em>:<\/p>\n Create new Custom JavaScript Macro<\/p>\n<\/li>\n Add the following code:<\/p>\n<\/li>\n<\/ol>\n Well it\u2019s easy to credit where I got the idea for this one. Google uses a version of this as an example of the Custom JavaScript Macro:<\/p>\n <\/p>\n <\/a><\/p>\n<\/div>\n The idea behind this macro is that it returns the time (hours) of the client<\/em> as opposed to the time of the website (i.e. server), which is what\u2019s measured by default.<\/p>\n So if you\u2019re interested in what the local time (in hours) is of the visitor, use this macro and store it as a custom dimension, for example.<\/p>\n Macro Type<\/strong>: Random Number<\/a> Instructions and description<\/em>:<\/p>\n OK, so the macro isn\u2019t difficult at all to create, nor is it anything magical (YET!). But this is a beautiful scenario for something as simple as the Random Number macro (which, I\u2019m sure, is often very neglected). This idea comes directly from Dan Russell, and you can read about this in his original blog post<\/p>\n Sampling a percentage of your users with Google Tag Manager<\/a>.<\/p>\n The sweetness is not in the macro but in the rule which you\u2019ll use to fire your tags. If you want to fire a tag for every 10th visitor, you\u2019d add a rule with the following condition:<\/p>\n {{Random Number Macro}} ends with 3<\/strong><\/p>\n If you want to fire a tag for every 100th visitor, you\u2019d edit the rule so that it\u2019s:<\/p>\n {{Random Number Macro}} ends with 01<\/strong><\/p>\n It\u2019s so simple and beautiful. Because the Random Number macro returns a random number, you can assume that there\u2019s roughly a 1\/10 chance that the number will end in 3, and roughly a 1\/100 chance that it will end in 01.<\/p>\n How\u2019s that for pre-sampling your data before Google Analytics gets to work on it with its brutal thresholds<\/a>?<\/p>\n Macro Type<\/strong>: Custom JavaScript<\/a> Instructions and description<\/em>:<\/p>\n Create Custom JavaScript Macro<\/p>\n<\/li>\n Add following code:<\/p>\n<\/li>\n<\/ol>\n This macro came from St\u00e9phane Hamel, in another inspiring, \u201ccrowd-sourced\u201d Google+ discussion<\/a>. The idea is that when a Link Click Listener is activated, this macro will return the file extension of the clicked link, and if one doesn\u2019t exist, it returns just html<\/strong>. So if the link was to You can use this in your tags either as a rule or as a value for a specific field. For example, here\u2019s an event tag which sends the extension of the clicked link as one of the parameters:<\/p>\n <\/p>\n <\/a><\/p>\n<\/div>\n If the link were to http:\/\/www.mydomain.com\/brochure.pdf,<\/a> this tag would fire with:<\/p>\n Event Category \u201cpdf link click\u201d Macro Type<\/strong>: Custom JavaScript<\/a> Instructions and description<\/em>:<\/p>\n Create Custom JavaScript Macro<\/p>\n<\/li>\n Add following code:<\/p>\n<\/li>\n<\/ol>\n This macro is very similar to the previous one, except now it returns the whole file name. If the downloaded link is not an asset with a file extension, the script returns the ambiguous \u201cn\/a\u201d string, which can be used in blocking rules, for example.<\/p>\n Use this macro to make your link click event tags more dynamic. In the best case scenario, you\u2019ll just need one event tag for all your link clicks, because variable value macros like this are what make your tags the dynamic vessels they should be.<\/p>\n Macro Type<\/strong>: Custom JavaScript<\/a> Instructions and description<\/em>:<\/p>\n Create Custom JavaScript macro<\/p>\n<\/li>\n Add following code within:<\/p>\n<\/li>\n<\/ol>\n This returns true<\/strong> if the clicked element URL contains the hostname of the current page, and false<\/strong>, if the clicked element URL contains some other hostname.<\/p>\n You can use this in your firing rules, e.g. fire an \u201cOutbound link\u201d event only when the clicked link is not internal:<\/p>\n <\/p>\n <\/a><\/p>\n<\/div>\n Macro Type<\/strong>: 1st Party Cookie<\/a>, Custom JavaScript<\/a> Instructions and description<\/em>:<\/p>\n Create 1st Party Cookie macro<\/p>\n<\/li>\n Set cookie name to _ga<\/strong><\/p>\n<\/li>\n Create Custom JavaScript macro<\/p>\n<\/li>\n Add following code within:<\/p>\n<\/li>\n<\/ol>\n First you create a new 1st Party Cookie macro, which returns the value of the _ga cookie. It might be something like GA1.2.475226310.1380715146<\/strong>. Next, the Custom JavaScript macro parses this string, and returns the third (client ID) and fourth (timestamp) elements of the cookie value (475226310.1380715146<\/strong>), which combine to make the complete clientID of the user.<\/p>\n You can then add this as a session-level custom dimension, for example, to identify which clientID committed to what actions on your site during their session. You could then use the Measurement Protocol<\/a> to work all sorts of offline-online data stitching magic with your database tools!<\/p>\n Note that I use a very rudimentary try-catch block for error handling. Feel free to handle errors in any way you want (as long as you do handle them!).<\/p>\n Macro Type<\/strong>: Custom JavaScript<\/a> Instructions and description<\/em>:<\/p>\n Create Custom JavaScript macro<\/p>\n<\/li>\n Add following code within:<\/p>\n<\/li>\n<\/ol>\n This is Google\u2019s recommendation for fetching the client ID (rather than parsing the cookie). You basically access the ga<\/strong> object using the function getAll()<\/em>. This would normally retrieve all named trackers, but you\u2019re only interested in the first one (which is the one GTM sets). Finally, it uses the get<\/em> method of the tracker object to retrieve the value of the property clientId<\/em>, which is, coincidentally, the clientId.<\/p>\n NOTE!<\/strong> This macro will not work if it fires before a page view is sent. The tracker is created during the page view call, so you\u2019ll either have to use a callback function (see the next section) or have the tag which fetches the client ID fire upon {{event}} equals gtm.load<\/strong>.<\/p>\n Macro Type<\/strong>: Custom JavaScript<\/a> Instructions and description<\/em>:<\/p>\n Create Custom JavaScript macro<\/p>\n<\/li>\n Add following code within:<\/p>\n<\/li>\n<\/ol>\n The Universal Analytics tag doesn\u2019t have a callback field that you can use (yet). So you\u2019ll have to resort to the \u201cFields to set\u201d option, and add the callback function manually.<\/p>\n Anyway, the idea with hitCallback is to do something as soon as the tag has fired. In my example, I push an event called \u2018pageViewFired\u2019, which I can then use in some other tag to make sure it fires only after the page view has been sent. You\u2019d need to add the macro to your tag like this:<\/p>\n <\/p>\n <\/a><\/p>\n<\/div>\n The field to set is called hitCallback<\/strong> and its value should be the macro you just created.<\/p>\n If you look at the code, you\u2019ll see a funny thing. You\u2019re returning<\/em> the function which does all the work. Why, you wonder? Simple. When the event tag is fired, it will go through all the fields that have been set for the tag, performing all the actions within. If you didn\u2019t have the function returning another function, the callback would fire twice<\/strong>: first when the event tag\u2019s firing begins, and again when the tag has completed (when the callback function is actually called).<\/p>\n This might be a bit difficult to fathom, but it\u2019s just how GTM and JavaScript work. hitCallback is expecting a function, so the function in your callback tag has to return<\/em> a function, because macros need to always return something.<\/p>\n Messy. But it works!<\/p>\n Macro Type<\/strong>: Custom JavaScript<\/a> Instructions and description<\/em>:<\/p>\n Create Custom JavaScript macro<\/p>\n<\/li>\n Add following code within:<\/p>\n<\/li>\n<\/ol>\n This is a very simple macro. There\u2019s no predefined macro for you to use if you want to return the url pathname with query parameters. This macro does just that.<\/p>\n Macro Type<\/strong>: Lookup Table<\/a> Instructions and description<\/em>:<\/p>\n Create a Lookup Table macro<\/p>\n<\/li>\n Add some tracking code as the Default Value (optional)<\/p>\n<\/li>\n In the first column, choose {{url hostname}} as the macro that is evaluated<\/p>\n<\/li>\n In the first column, add all the different hostnames you want to assign a property ID to<\/p>\n<\/li>\n In the second column, add the respective property ID for each hostname<\/p>\n<\/li>\n<\/ol>\n This is a very useful macro if you have multiple domains with different property IDs tracked by the same container. Whenever you have the same tags running on all the different domains, using a lookup like this means you don\u2019t have to create a separate tag for each ID.<\/p>\n The macro should look like this:<\/p>\n ![\"Simo](\"https:\/\/www.simoahava.com\/images\/2014\/03\/measurecamp.jpg#ZgotmplZ\")
<\/p>\n
\n X<\/span><\/p>\n
\n The Simmer Newsletter<\/strong>\n <\/p>\nIntroducing Macro Magic<\/h2>\n
![\"Macro](\"https:\/\/www.simoahava.com\/images\/2014\/03\/macro-magic.jpg#ZgotmplZ\")
<\/p>\n1. Client time<\/h2>\n
Use for<\/strong>: To get local time of client<\/em> as opposed to the the time of the web server hosting the site.
Example return value<\/strong>: 11<\/p>\n\n
function<\/span>() {\n var<\/span> now = new<\/span> Date<\/span>();\n return<\/span> now.getHours();\n}\n<\/code><\/pre>\n<\/div>\n![\"Client](\"https:\/\/www.simoahava.com\/images\/2014\/03\/client-time.jpg#ZgotmplZ\")
<\/p>\n2. Random number for sampling<\/h2>\n
Use for<\/strong>: To fire a tag only for every 10th visitor, for example
Example return value<\/strong>: 647156<\/p>\n\n
3. Return file extension of clicked link<\/h2>\n
Other requirements<\/strong>: Macro for Auto-Event Variable<\/a> of type Element (named {{element}} in this example)
Use for<\/strong>: Rules, event fields
Example return value<\/strong>: pdf<\/p>\n\n
function<\/span>() {\n var<\/span> ext = {{element}}.pathname.split(\".\"<\/span>);\n return<\/span> ext.length > 1<\/span>?ext.pop():'html'<\/span>;\n}\n<\/code><\/pre>\n<\/div>\nhttp:\/\/www.mydomain.com\/brochure.pdf<\/code>, this macro will return pdf<\/strong>.<\/p>\n![\"Filetype](\"https:\/\/www.simoahava.com\/images\/2014\/03\/event-filetype.jpg#ZgotmplZ\")
<\/p>\n
Event Action \u201cbrochure.pdf\u201d (more on this in the next chapter)
Event Label \u201curl of page where brochure.pdf was downloaded from<\/em>\u201d<\/p>\n4. Return file name of clicked link<\/h2>\n
\nOther requirements<\/strong>: Macro for Auto-Event Variable<\/a> of type Element (named {{element}} in this example)
Use for<\/strong>: Event fields
Example return value<\/strong>: brochure.pdf<\/p>\n\n
function<\/span>() {\n var<\/span> filepath = {{element}}.pathname.split(\"\/\"<\/span>);\n var<\/span> filename = filepath.pop();\n return<\/span> filename.indexOf(\".\"<\/span>) > -1<\/span>?filename:'n\/a'<\/span>;\n}\n<\/code><\/pre>\n<\/div>\n5. Check if clicked link is internal<\/h2>\n
Other requirements<\/strong>: Macro for Auto-Event Variable<\/a> of type Element URL (named {{element url}} in this example), macro for URL<\/a> of type URL Hostname (named {{url hostname}} in this example)
Use for<\/strong>: Firing rules
Example return value<\/strong>: true<\/p>\n\n
function<\/span>() {\n return<\/span> {{element url}}.indexOf({{url hostname}}) > -1<\/span>;\n}\n<\/code><\/pre>\n<\/div>\n![\"Outbound](\"https:\/\/www.simoahava.com\/images\/2014\/03\/outbound-link.jpg#ZgotmplZ\")
<\/p>\n6. Get clientID using _ga cookie<\/h2>\n
Other requirements<\/strong>: Universal Analytics property
Use for<\/strong>: Offline measurement, stitching client data
Example return value<\/strong>: 475226310.1380715146<\/p>\n\n
function<\/span>() {\n try<\/span> {\n var<\/span> cookie = {{ga cookie}}.split(\".\"<\/span>);\n return<\/span> cookie[2<\/span>] + \".\"<\/span> + cookie[3<\/span>];\n } catch<\/span>(e) {\n console.log(\"No Universal Analytics cookie found\"<\/span>);\n }\n}\n<\/code><\/pre>\n<\/div>\n7. Get clientID using ga.getAll()<\/h2>\n
Other requirements<\/strong>: Universal Analytics property
Use for<\/strong>: Offline measurement, stitching client data
Example return value<\/strong>: 475226310.1380715146<\/p>\n\n
function<\/span>() {\n try<\/span> {\n var<\/span> tracker = ga.getAll()[0<\/span>];\n return<\/span> tracker.get('clientId'<\/span>);\n } catch<\/span>(e) {\n console.log(\"Error fetching clientId\"<\/span>);\n }\n}\n<\/code><\/pre>\n<\/div>\n8. hitCallback with a Universal Analytics tag<\/h2>\n
Use for<\/strong>: Imposing a tag firing order<\/p>\n\n
function<\/span>() {\n return<\/span> function<\/span>(){dataLayer.push({'event'<\/span>: 'pageViewFired'<\/span>});}\n}\n<\/code><\/pre>\n<\/div>\n![\"hitCallback](\"https:\/\/www.simoahava.com\/images\/2014\/03\/hitcallback.jpg#ZgotmplZ\")
<\/p>\n9. Return URL path + query string<\/h2>\n
Use for<\/strong>: Working with the query string
Example return value<\/strong>: \/analytics\/?internal=true<\/p>\n\n
function<\/span>() {\n return<\/span> location.pathname+location.search;\n}\n<\/code><\/pre>\n<\/div>\n10. Property ID lookup with hostname<\/h2>\n
Other requirements<\/strong>: Macro for URL<\/a> of type URL Hostname (named {{url hostname}} in this example)
Use for<\/strong>: To have the same tracking tag for different property IDs on different domains
Example return value<\/strong>: UA-12345-1<\/p>\n\n