Definition
MSCLKID is the click identifier appended by Microsoft Ads (Bing) to attribute sessions and conversions back to ads.
Example
A landing page URL includes -msclkid=... so the click can be tied to a conversion upload.
How to use it
- Keep MSCLKID through redirects and analytics tracking.
- Use UTMs as the human-readable layer; click IDs are the machine layer.
- Store the ID only as long as needed for attribution and offline conversion matching.
Common mistakes
- Stripping query parameters during redirects and losing attribution.
- Relying only on click IDs without consistent UTMs for reporting.
Measured as
Measure MSCLKID (Microsoft Click ID) with a fixed attribution window, conversion event, and spend basis before comparing campaigns or creative tests.
Misused when
- Stripping query parameters during redirects and losing attribution.
- Relying only on click IDs without consistent UTMs for reporting.
Operator takeaway
- Keep MSCLKID through redirects and analytics tracking.
- Use UTMs as the human-readable layer; click IDs are the machine layer.
- Store the ID only as long as needed for attribution and offline conversion matching.
- Use MSCLKID (Microsoft Click ID) only inside a stable attribution rule, conversion definition, and time window so campaign comparisons stay honest.
- If performance changes, check whether the metric moved for a real business reason or because the measurement setup changed underneath you.
Next decision
- Read UTM + GA4 attribution: practical tracking for paid ads (without lying to yourself) if the decision depends on interpretation, policy, or trade-offs beyond the raw formula.
- Decide which report owns MSCLKID (Microsoft Click ID) before comparing campaigns, channels, or creative tests.
Where to use this on MetricKit
Guides
- UTM + GA4 attribution: practical tracking for paid ads (without lying to yourself): A practical guide to UTMs and GA4: consistent source/medium/campaign tagging, conversion deduplication, and common attribution traps.