Definition
Auction overlap measures how often your ads compete in the same auctions as another advertiser. It can explain CPM/CPC pressure and ranking dynamics.
How to use it
- Use overlap and outranking share to understand competitive pressure.
- Do not chase impression share blindly; use marginal ROAS and profit constraints.
Measured as
Measure Auction Overlap with a fixed attribution window, conversion event, and spend basis before comparing campaigns or creative tests.
Operator takeaway
- Use overlap and outranking share to understand competitive pressure.
- Do not chase impression share blindly; use marginal ROAS and profit constraints.
- Use Auction Overlap 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 Marginal ROAS: how to scale ads with diminishing returns if the decision depends on interpretation, policy, or trade-offs beyond the raw formula.
- Decide which report owns Auction Overlap before comparing campaigns, channels, or creative tests.
Where to use this on MetricKit
Guides
- Marginal ROAS: how to scale ads with diminishing returns: A practical guide to marginal ROAS: why average ROAS misleads at scale, how diminishing returns work, and how to pick a profit-maximizing spend level.
- Paid ads bidding & budgeting hub: max CPC, target CPA, and break-even targets: A practical hub for bidding and budgeting: compute max CPC from CVR and margin, set target CPA using LTV, and use break-even CTR/CVR/CPM targets to guide creative and landing optimizations.