9 Click ID and their Ad Platforms [With Example]

A click ID is an opaque token that an ad platform appends to your landing URL when someone clicks one of your ads. Different platforms use different names, all of them serve the same purpose: a high-confidence proof that “this visit came from this ad.”

For attribution accuracy, click IDs do three things UTMs alone can’t:

1. Survive privacy stripping. Some iOS browsers and ad blockers remove the Referer header but leave query strings intact. The click ID hangs on.
2. Encode platform-specific data the ad network can decode. Pushing an offline conversion back to Google Ads with the original gclid lets Google match the conversion to the exact campaign, ad group, keyword, audience, and creative the click came from, depth no UTM can carry.
3. Are set automatically. Auto-tagging is on by default in most ad accounts, so click IDs land on every paid click without per-campaign URL-tagging discipline.

This article lists every click ID SourceLoop reads, what platform sets it, and what channel it implies.

The full table

Click ID	Platform	Channel	Notes
gclid	Google Ads	Paid Search	The classic Google Ads click ID. Set on every paid Google Search and Display click when auto-tagging is on.
gbraid	Google Ads (iOS)	Paid Search	iOS app campaigns when the user has restricted Apple’s App Tracking Transparency (ATT). Functionally equivalent to gclid for SourceLoop’s purposes.
wbraid	Google Ads (iOS web)	Paid Search	iOS web clicks under ATT restrictions. Functionally equivalent to gclid.
msclkid	Microsoft Ads (Bing)	Paid Search	The Microsoft equivalent of gclid. Set on every Microsoft Ads click when Final URL Auto-tagging is on.
fbclid	Meta (Facebook + Instagram)	Paid Social	Set on every click from inside Meta’s ecosystem, paid ads, organic posts, profile-bio links, Messenger shares. The presence of fbclid doesn’t strictly mean paid; it means the click originated from Meta.
li_fat_id	LinkedIn	Paid Social	LinkedIn’s First-Party Ads Tracking UUID. Set by the LinkedIn Insight Tag on the first paid-ad landing for a visitor; persists across sessions.
ttclid	TikTok	Paid Social	TikTok Ads click identifier.
epik	Pinterest	Paid Social	Pinterest Promoted Pin click identifier.
rdt_cid	Reddit	Paid Social	Reddit Ads click identifier.

How SourceLoop reads them

The tracker reads every click ID present on the landing URL and stores them on the visitor’s session and (on conversion) on the lead. From there:

• For channel classification, the click ID is the highest-confidence signal. A gclid on the URL means Paid Search even if the referrer is missing and no UTMs are set.
• For offline conversion sync, when you push a lead back to Google Ads / Microsoft Ads / Meta / LinkedIn, SourceLoop sends the stored click ID alongside the conversion so the platform can match it to the original click record.
• For lead detail and CSV export, all stored click IDs appear as columns on the lead row.

Why both UTM and click ID

UTMs and click IDs are complementary, not redundant. Each survives where the other fails:

Scenario	UTM survives?	Click ID survives?
iOS Safari with strict tracking prevention (referrer stripped)	✅ Yes	✅ Yes
URL shortener that strips query strings	❌ No	❌ No
Redirect chain that drops your custom params but keeps platform-set ones	❌ Often no	✅ Yes
Bookmarked URL revisited later (no original click)	❌ No	❌ No
Email forwarded with link intact	✅ Yes	✅ Yes
Ad platform auto-tagging is disabled	✅ Yes (if you set manual UTMs)	❌ No
You forgot to add UTMs to a paid campaign	❌ No	✅ Yes (auto-tagging)

The best practice is to run both: keep auto-tagging on in every ad account AND add manual UTMs (utm_source, utm_medium, utm_campaign) to every paid link.

Where click IDs power offline conversions

When you connect Google Ads, Microsoft Ads, Meta, or LinkedIn to SourceLoop and turn on offline-conversion sync, the lead’s stored click ID is what makes the round trip possible. The flow:

1. Visitor clicks a Google Ad. gclid=ABC... lands on the URL. SourceLoop stores it.
2. Visitor fills out a form. SourceLoop creates a lead with the gclid attached.
3. Sales qualifies the lead in your CRM.
4. SourceLoop’s sync to Google Ads fires an offline conversion event with the gclid and the lead value.
5. Google Ads receives the event, looks up the gclid to find the original click, and credits the conversion (with full revenue) to the right campaign, ad group, and keyword.

Without the click ID, the offline conversion still uploads (matched by hashed email instead), but Google’s match rate drops from ~99% to roughly 60-80%, and you lose campaign-level granularity.

See the per-platform guides:

• Configure Google Ads offline conversions
• Configure Microsoft Ads offline conversions
• Configure Meta Conversions API
• Configure LinkedIn offline conversions
• Configure TikTok Events API

How to verify click IDs are landing

The fastest way to check that auto-tagging is on and SourceLoop is picking up the click IDs:

1. Click one of your own live ads (preferably from an incognito window so the click isn’t deduped against your existing session).
2. After landing, look at the URL bar. You should see the click ID as a query parameter.
3. Open ?sl_debug=1 on the landing page and check the browser console; SourceLoop logs every captured click ID under the [sourceloop/v3] prefix.
4. Convert (submit a form or book a meeting) on the same session.
5. Open the lead in the SourceLoop Contacts Hub. The click ID is listed in the lead detail drawer under the technical/attribution panel.

If you can see the click ID on the URL but not on the lead, the most common cause is the tracker not loading on the landing page; double-check the tracking pixel install.

What’s next

• How click IDs feed into the channel decision: How SourceLoop classifies marketing channels.
• Set manual UTMs alongside click IDs: UTM best practices.
• Push the click IDs back to the ad platform for offline conversions: Configure Google Ads offline conversions, Configure Meta Conversions API, Configure LinkedIn offline conversions.