Target CPA and Maximize Conversions are both Google Ads Smart Bidding strategies, but they optimize for different goals. Target CPA aims to get conversions at a specific cost-per-acquisition you set, while Maximize Conversions spends your full budget to get as many conversions as possible regardless of cost per conversion. Target CPA prioritizes efficiency; Maximize Conversions prioritizes volume.

How Each Bidding Strategy Works

Both strategies use Google's machine learning to set bids in real time at auction. The difference is the objective each one optimizes toward.

Target CPA (tCPA)

Target CPA lets you set a goal cost per conversion. Google then adjusts bids automatically to hit that average CPA across all campaigns using the strategy. If you set a $50 target CPA, the system tries to keep your average acquisition cost near $50, raising bids on high-converting auctions and lowering them on weaker ones.

Key traits:

  • You control the cost efficiency by setting the target
  • Spend may not reach the full budget if Google can't find conversions at your target
  • Works best with steady conversion history (at least 15-30 conversions in the past 30 days)

Note: Google has folded standalone tCPA into Maximize Conversions with an optional target CPA setting in newer campaign types. The mechanics are the same, just packaged differently.

Maximize Conversions

Maximize Conversions spends your entire daily budget to drive the highest possible conversion count. It doesn't cap cost per conversion unless you add an optional target CPA. Without that target, the strategy will spend whatever it takes within budget to win conversions.

Key traits:

  • Optimizes for conversion volume, not cost control
  • Always tries to spend the full budget
  • Good for launching campaigns or capturing demand quickly
Side-by-side diagram comparing target CPA efficiency-focused bidding versus maximize conversions volume-focused bidding in Google Ads

Side-by-Side Comparison

FactorTarget CPAMaximize Conversions
Primary goalHit a cost-per-conversion targetGet the most conversions
Budget spendMay underspend to stay efficientSpends full daily budget
Cost controlHigh (you set the target)Low (unless tCPA added)
Best forMature campaigns with clear CPA goalsLaunches, demand capture, scaling
Data needed15-30+ recent conversionsSome conversion history helps
RiskMissed volume if target too lowHigh cost per conversion

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When to Use Target CPA

Choose Target CPA when you know your acceptable acquisition cost and need to protect margins. This fits performance marketers running lead gen or e-commerce with a clear unit economics model. If a lead is worth $200 and you want a 4:1 return, a $50 tCPA makes sense.

Set your target too low and Google may throttle spend, leaving budget unused. Most teams get this wrong by setting an aggressive target before the campaign has enough conversion data to optimize. Google's Smart Bidding documentation recommends letting the strategy gather data for at least a week before judging results.

When to Use Maximize Conversions

Pick Maximize Conversions when filling the pipeline matters more than per-conversion cost. New campaigns benefit because the strategy gathers data fast by spending aggressively. It's also useful when you have budget headroom and want to capture every available conversion in a competitive market.

If you're building out a B2B sales and demand generation motion, Maximize Conversions can flood the top of funnel early, then you switch to Target CPA once you understand your real cost per qualified lead.

How They Affect Lead Quality

Neither strategy optimizes for lead quality by default. Both count whatever conversion action you've configured. If your conversion is a low-intent form fill, Maximize Conversions can produce high volume with poor quality, and Target CPA will chase cheap conversions that may not close.