Platform attribution

Meta, Google, TikTok each have their own attribution systems. They report different numbers for the same conversions. Understanding what each captures (and misses) keeps you from over-trusting any one.

Meta attribution

• Default: 7-day click, 1-day view
• Alternatives: 1-day click only (iOS-friendly)
• Includes: conversions attributed to clicks within window + view-through
• Missing: iOS users without tracking, users in incognito, cross-device

Typical underreporting: 20-40% of real conversions.

Google Ads attribution

• Default: data-driven attribution (DDA)
• Older: last-click, first-click, linear
• Includes: conversions up to 30 days after click
• Better than Meta because of Google's better identity signals (logged-in users)

TikTok attribution

• 7-day click, 1-day view by default
• Newer system, still maturing
• Often underreports significantly

The overlap problem

User sees Meta ad, then Google ad, then converts. Both platforms claim the conversion. If you believe both reports, you double-count. Your real-world total revenue doesn't match.

The fix: blended measurement

• Total ad spend across all channels
• Total new customers
• Blended CAC = total spend / total customers

This is the truth. Channel-specific numbers are directional.

The MER metric

Media Efficiency Ratio = Total revenue / Total ad spend. Blended, simple, true. Most mature advertisers track this alongside channel-specific metrics.

How to use platform attribution

• For relative comparison: "is this campaign better or worse than yesterday?" Platform attribution works.
• For absolute truth: "how much are we spending per customer?" Use blended.
• For budget allocation: use platform data plus lift tests.