How to capture the GCLID in Calendly
Use Attributer to capture the GCLID with each Calendly booking and send it to your CRM and other tools (and back to Google Ads).
Attributer makes it easy to capture the GCLID in Calendly. Simply add it to your UTM parameters and Attributer captures it and passes it through with each booking. It also pulls in UTM parameters and other attribution data at the same time.
Struggling to figure out which Google Ads campaigns are actually driving leads and customers? You're not alone.
Google Analytics can tell you how many people clicked your ads and visited your site, but it can't tell you which of those visitors actually booked a meeting or became a paying customer. And without that visibility, it's really difficult to know if your ad spend is working or where to invest more budget.
The good news? There's a solution.
In this article, I'll show you how to use Attributer to capture the GCLID with every Calendly booking, and then send that data to your CRM and back to Google Ads as an offline conversion.
3 steps for capturing the GCLID in Calendly
Capturing the GCLID with every Calendly booking is simple with Attributer. Here's how to do it:
1. Add the GCLID to your UTM Parameters
Calendly has built-in ability to capture UTM parameters, but it doesn't have the ability to add hidden fields to capture custom information (like the GCLID).
Therefore, the first thing you need to do is make sure the GCLID is being added to the UTM parameters you put behind your ads.
The easiest way to do this is to use the {gclid} ValueTrack parameter. This is basically a little variable you put in your UTMs that then gets overwritten with the actual GCLID.
So if you put the following UTMs behind your ad:
https://mysite.com?utm_term={gclid}
The visitor who clicked your ad would actually arrive at the following URL:
https://mysite.com?utm_term=6346536875
2. Attributer stores the GCLID and passes it through with each booking
When someone clicks one of your Google Ads and arrives on your site, Attributer picks up the GCLID from the URL and stores it in their browser (which means they can browse around your site or even leave and come back later, and the GCLID is still remembered).
Then, when they complete one of the Calendly booking widgets on your website, Attributer writes the data into the hidden UTM fields.
3. GCLID is captured with each form submission
When someone completes a booking, Calendly captures the GCLID alongside all the other details the invitee provided, like their name, email, and phone number.
You can then view it in the Scheduled Events section of your Calendly dashboard, and it will be included in any booking notification emails you have set up.
From there, you can use Calendly's native integrations or tools like Zapier or Make to send the data straight into your CRM or any other tools you need it in.
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'll need to set up a new conversion action.
To do that, log into Google Ads and click Goals in the left sidebar, then navigate to Conversions. From there, click the button to create a new conversion, select Imported from the options, then 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 live in Google Ads, you need to decide which stage of your sales process should trigger the GCLID being sent back. This decision matters more than most people think.
Many businesses wait until a deal is closed before sending the conversion back to Google. It seems logical, but it can actually work against you. Google's smart bidding strategies (like Maximise Conversions, Maximise Conversion Value, or Target CPA) generally need at least 50 conversions per month to work properly.
If you're not closing 50 deals a month, you'll get better results by triggering the conversion at an earlier stage in your pipeline, like when a new deal is created in your CRM. You're still giving Google a meaningful signal (a lead your sales team has actually qualified) while providing smart bidding enough volume to operate effectively.
Once you've settled on your trigger point, head into Zapier and create a new Zap. Set the trigger to match whatever moment you decided on. 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 Calendly
There are other ways to capture the GCLID with Calendly bookings, so what makes Attributer worth choosing over the alternatives?
Here's why 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 exact same page they originally landed on.
That's a real problem.Imagine someone clicks your Google Ad and lands on your homepage, but then moves over to your Contact Us page and books a call there. By the time they navigate there and complete the booking, the GCLID is gone from the URL and it never gets captured.
Attributer works differently. It saves the GCLID in the visitor's browser the moment they land on your site, so it doesn't matter which page they end up booking on, or even if they leave and return later. The GCLID gets captured every single time.
2. Captures UTM parameters as well
Attributer doesn't just capture the GCLID. It also captures any UTM parameters you've added to your campaigns.
For example, say you're running ads for an architecture firm. When someone clicks one of your Google Ads and completes a Calendly booking, Attributer would write the following into the hidden fields alongside the GCLID:
- Channel = Paid Search
- Channel Drilldown 1 = Google
- Channel Drilldown 2 = Residential Architecture Campaign
- Channel Drilldown 3 = Home Architect Sydney
- Channel Drilldown 4 = Free Consultation Ad
3. Captures information on users from organic channels
Attributer also captures attribution data for visitors who arrive through organic channels like Organic Search, Organic Social, Referral, or Direct Traffic.
Sticking with the architecture firm 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 = Residential Architect Sydney (or whatever keyword they searched for, if it's available)
How Attributer helped Harris Federal Law track which Google Ads are truly generating customers & revenue
Harris Federal Law Firm is a legal practice in Washington D.C. that helps federal employees secure their benefits.
They were investing serious money into Google Ads and monitoring traffic through Google Analytics, but there was a significant gap in their data. They had no way of knowing which visitors were actually turning into leads and paying clients.
That's when they found Attributer.
Once it was set up, Attributer started capturing attribution details like campaign, ad group, ad, keyword, and GCLID with every Calendly booking on their site. That data was sent straight to their CRM alongside each lead's contact information.
For the first time, the team could run reports showing exactly which campaigns were generating real paying clients and which ones were burning through budget without delivering results.
The biggest discovery? Several of their display campaigns were pulling in plenty of traffic but converting almost nobody into actual clients. Armed with that information, they shifted budget toward the search campaigns that were genuinely driving new business.
The outcome was more customers at 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 Calendly booking and send it to your CRM so you can fire offline conversions back to Google Ads? Attributer makes it simple.
It saves the GCLID the moment a visitor lands on your site and holds onto it as they browse around, even if they leave and come back days later. That way, the GCLID gets captured with every single booking, no matter what.
Best of all, it's free to get started and you can be up and running in under 10 minutes. Start your 14 day free trial today and start capturing the GCLID with Calendly right away.
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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.