Deliver relevant advertisements, limit repeated ad displays, and measure the effectiveness of advertising campaigns.
__gads
Google Ads — ad personalisation, campaign tracking, delivery/frequency capping (covers __gpi, __eoi, _gcl_au).
13 months
MR
Microsoft/Bing Ads campaign performance tracking (covers SRM_B, MUID on bing.com).
Varies
test_cookie
DoubleClick — checks third-party cookie support.
1 day
aplo-intent-pixel
Aplo intent-data/marketing tracking pixel.
N/A
adroll-exchange-partners
AdRoll's ad-exchange cookie-sync partners (3lift, Xandr, Sharethrough, Agkn, Eyeota, PubMatic, OpenX, Taboola, Outbrain).
N/A
zoho-google-ads-combined
Combined custom GTM tag mixing Zoho and Google Ads tracking code.
N/A
TDCPM
The Trade Desk — programmatic ad bidding/targeting (covers TDID).
1 year
TapAd_3WAY_SYNCS
Tapad — cross-device identity graph for ad targeting (covers TapAd_DID, TapAd_T).
Varies
_rdt_uuid
Reddit Ads conversion pixel.
3 months
linkedin-gtm-tags
Additional LinkedIn GTM tags — 3 separate LinkedIn tags total.
N/A
bcookie
LinkedIn Insight Tag — ad conversions, audience building (covers li_sugr, lidc, li_adsId)
Varies
facebook-pixel
Meta/Facebook Pixel — ad conversion tracking and retargeting (2 tag instances confirmed in GTM).
N/A
__adroll
AdRoll retargeting, cross-device tracking, and campaign attribution (covers __adroll_fpc, __adroll_shared, __ar_v4, adroll_dqs, adroll_flgs).
1 year
gclid (uncategorised, discovered)
Google Ads click ID parameter.
1 month