Target CPA is a smart-bidding strategy on Google Ads (and historically Meta) where you tell the platform a target CPA — say €40 — and the algorithm optimises bids to win impressions for users it predicts will convert at-or-near that target. The platform sacrifices reach for efficiency: it only bids when the predicted CPA is acceptable.
When it works
- After a campaign has accumulated 30+ conversions in the last 30 days — algorithm needs signal
- When your conversion event is a real revenue-bearing outcome, not a soft micro-conversion that doesn't predict revenue
- When your target is realistic — set it 10-20% above the campaign's recent average CPA, not 50% below
When it breaks
- Set the target too aggressively and the algorithm will throttle delivery to near-zero — a 'no-spend' day means the target is unreachable
- Pre-iOS conversion data underrepresents reality post-iOS — your historical CPA may be inflated and the algorithm calibrates against the wrong number
- Brand-new campaigns with no data; tCPA needs to learn before it can hit the target
vs Maximize Conversions
Maximize Conversions spends the budget regardless of CPA — get me as many conversions as possible. Target CPA conserves budget if the target isn't achievable. Operators usually start a new campaign with Maximize Conversions for 2-4 weeks to gather data, then switch to Target CPA once they know what their floor is.