How to capture the GCLID in Cal
Use Attributer to capture the GCLID in Cal.com and send it to your CRM and other tools (and back to Google Ads).
Attributer makes it simple to capture the GCLID in Cal. Simply add some hidden fields to your Cal form, and Attributer will grab the GCLID and send it through with every new booking. On top of that, it also captures UTM parameters and other attribution data on your leads.
Finding it hard to figure out which of your Google Ads campaigns are actually generating leads and customers? You're not alone.
Tools like Google Analytics can show you how many people clicked on your ads and landed on your site, but they can't tell you which of those visitors actually booked a meeting or turned into a paying customer. Without that information, it's tough to know whether your ad spend is delivering results or where you should be putting more budget.
The good news? There's a solution.
In this article, we'll show you how to use Attributer to capture the GCLID with every Cal booking, then send that data to your CRM and back to Google Ads as an offline conversion.
3 steps for capturing the GCLID in Cal
Capturing the GCLID with every Cal booking is easy with Attributer. Here's how to get it set up:
1. Install Attributer and add hidden fields to Cal
Sign up for a 14 day free trial of Attributer and you'll get a small snippet of code to add to your website.
Installing it on your site is quick and easy. The exact process depends on what platform your site is built on (WordPress, Webflow, Squarespace, etc.), but you can generally add it through the settings section of your website builder.
Once the code is installed, you'll need to add a hidden field to your Cal booking form. Just create a new hidden field and name it "GCLID". This gives Attributer a place to write the GCLID so it gets captured with every new booking.
If you need a hand getting set up, full step by step instructions are available here.
2. Attributer stores the GCLID and passes it through with each booking
When someone clicks on one of your Google Ads and lands on your site, Attributer grabs the GCLID from the URL and stores it in their browser. This means they can browse around your site, or even leave and come back another day, and the GCLID is still there.
Then, when they complete a Cal booking form on your website, Attributer writes the GCLID into the hidden field on your form.
3. GCLID is captured with each form submission
When someone completes a booking, Cal captures the GCLID along with all the other details the person provided, like their name, email, and phone number.
You can then see it in the Bookings section of your Cal dashboard, and it will also be included in any booking notification emails you have set up.
From there, you can use Cal's built in integrations or third party tools like Zapier or Make to send the data straight to your CRM or any other tools you use.
How to send the GCLID back to Google Ads and mark it as an offline conversion
Before you can send the GCLID back to Google Ads, you need to set up a new conversion action.
To do this, log into Google Ads and click Goals in the left sidebar, then go to Conversions. From there, click the button to create a new conversion, select Imported from the options, and choose CRMs, files, or other data sources.
Then, in the final screen when it asks you to add a data source, select the option to ‘Add data source later’.
Once your conversion action is set up in Google Ads, the next step is to decide which stage of your sales process should trigger the GCLID being sent back. This decision is more important than most people realize.
A lot of businesses wait until a deal is closed before sending the conversion back to Google. It makes sense on the surface, but it can actually hurt your results. Google's smart bidding strategies (like Maximise Conversions, Maximise Conversion Value, or Target CPA) typically need at least 50 conversions per month to work effectively.
So if you're not closing 50 deals a month, you'll likely see better performance by triggering the conversion at an earlier stage in your pipeline, like when a new deal is created in your CRM. That way, you're still sending Google a meaningful signal (a lead your sales team has actually qualified) while giving smart bidding enough data to do its job properly.
Once you've decided on your trigger point, head into Zapier and create a new Zap. Set the trigger to match the moment you chose. For example, if you want the offline conversion to fire when a new deal is created in your CRM, use that as your trigger event.
Next, select Google Ads as the Action and then select the ‘Send Offline Conversion’ as the event.
Finally, you just need to map the GCLID from your CRM (or wherever you are storing it) to the correct field in Zapier.
That’s it! You have now set up offline conversions in Google Ads. It’s a good idea to test it’s working before piling money into ads, and you can read more about how to do that here.
Why Attributer is the best way to capture the GCLID in Cal
There are other ways to capture the GCLID with Cal bookings, so why use Attributer over the alternatives?
Here are a few reasons it stands out:
1. Remembers the GCLID as visitors browse your site
Most other methods for capturing the GCLID only work if the visitor books a meeting on the same page they originally landed on.
That's a real problem. If someone clicks your Google Ad and lands on your homepage, but then navigates over to your Contact Us page to book a call, then the GCLID is no longer in the URL and it never gets captured.
Attributer handles this differently. It stores the GCLID in the visitor's browser the moment they arrive on your site, so it doesn't matter which page they end up booking on, or even if they leave and come back days later. The GCLID is captured every single time.
2. Captures UTM parameters as well
Attributer doesn't just capture the GCLID. It also grabs any UTM parameters you've added to your campaigns.
For example, let's say you run a fencing company. When someone clicks one of your Google Ads and completes a Cal booking, Attributer would write the following into the hidden fields alongside the GCLID:
- Channel = Paid Search
- Channel Drilldown 1 = Google
- Channel Drilldown 2 = Timber Fencing Campaign
- Channel Drilldown 3 = Fence Installation Sydney
- Channel Drilldown 4 = Free Quote Ad
3. Captures information on users from organic channels
Attributer also captures attribution data for visitors who come through organic channels like Organic Search, Organic Social, Referral, or Direct Traffic.
Sticking with the fencing company example, if someone finds your site through a regular Google search rather than a paid ad, Attributer would pass through something like this:
- Channel = Organic Search
- Channel Drilldown 1 = Google
- Channel Drilldown 2 = www.google.com (or whichever search engine domain they came from)
- Channel Drilldown 3 = Timber fencing installation Sydney (or whatever keyword they searched, if available)
How Attributer helped Harris Federal Law track which Google Ads are truly generating customers & revenue
Harris Federal Law Firm is a legal practice based in Washington D.C. that specializes in helping federal employees secure their benefits.
They were pouring serious money into Google Ads and keeping an eye on website traffic through Google Analytics, but there was a big gap in what they could actually see. They knew how many visitors their ads were sending to the site, but they had no way of connecting those visitors to the leads and paying clients coming through the door.
Then they found Attributer.
After getting it set up, Attributer began capturing key attribution data (campaign, ad group, ad, keyword, and GCLID) with every lead that came through their website. All of that information was automatically passed into their CRM alongside each new lead's contact details.
For the first time, they could actually see which campaigns were producing paying clients and which ones were just burning through budget with nothing to show for it.
The biggest eye opener? Some of their display campaigns were generating tons of website traffic but were hardly turning any of those visitors into clients. Once they had that data in hand, they moved budget into the search campaigns that were actually driving new business.
The end result? More customers and a lower cost per acquisition.
"With Attributer we can see which campaigns are actually generating customers & revenue, rather than just website visitors. We were able to see that some of our campaigns were driving lots of visitors but few of them converted into leads and customers. Now we’re able to reinvest that budget into other campaigns that we can see are generating revenue."
Nick Child - Director of Marketing, Harris Federal Law Firm
Wrap Up
Want to capture the GCLID with every Cal booking and send it to your CRM so you can fire offline conversions back to Google Ads? Attributer makes it easy.
It stores the GCLID as soon as a visitor arrives on your site and keeps it saved as they browse around, even if they leave and come back days later. That means the GCLID is captured with every single booking, no matter what page they end up on.
Best of all, it's free to get started and setup takes less than 10 minutes. Start your 14 day free trial today and start capturing the GCLID with every Cal booking right away.
Get Started For Free
Start your 14-day free trial of Attributer today!
About the Author
Aaron Beashel is the founder of Attributer and has over 15 years of experience in marketing & analytics. He is a recognized expert in the subject and has written articles for leading websites such as Hubspot, Zapier, Search Engine Journal, Buffer, Unbounce & more. Learn more about Aaron here.