Definition
Server-side tagging routes tracking events through your server or a server-side tag container to reduce loss from blockers and improve control.
Example
A purchase event is sent from your server with a consistent event ID, then forwarded to ad platforms.
How to use it
- Use it to improve event reliability and to enforce consistent event schemas.
- Always implement event deduplication if you also send browser events.
- Audit server latency so conversion events arrive within platform windows.
Common mistakes
- Assuming server-side means no privacy or consent requirements.
- Breaking attribution by stripping query parameters in redirects.
- Forwarding events without validating required fields (value, currency).
Why this matters
This term matters because it affects how you interpret performance and make budget decisions. If you use inconsistent definitions or windows, ROAS/CPA can look "better" while profit gets worse.
Practical checklist
- Write a 1-line definition for "Server-side Tagging" that your team will use consistently.
- Keep the time window consistent (weekly/monthly/quarterly) when comparing trends.
- Segment results (channel/plan/cohort) before drawing big conclusions from blended averages.
- Sanity-check with a related calculator from the same category on MetricKit.
- Read the related guide (e.g., UTM + GA4 attribution: practical tracking for paid ads (without lying to yourself)) for context and common pitfalls.
Where to use this on MetricKit
Calculators
- Max CPC Calculator: Compute break-even and target CPC (and optional CPM) from CVR, AOV, and contribution margin assumptions.
- Break-even CPM Calculator: Compute break-even and target CPM from CTR, CVR, AOV, and contribution margin assumptions.
- Break-even CTR Calculator: Compute the CTR required to break even (and hit a target) given CPM, CVR, AOV, and contribution margin.
- A/B Test Sample Size Calculator: Estimate sample size per variant for a conversion rate A/B test given baseline CVR, MDE, significance, and power.
- CPL to CAC Calculator: Convert cost per lead (CPL) into CAC using lead-to-customer rate (and compute targets).
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.