How to Set Target ROAS in Google Ads: Calculate tROAS From Your Margin

How do you set a target ROAS? (Short answer)

Derive target ROAS from your own contribution margin, not from the account average or a rule of thumb like '400% is good'. Formula: Target ROAS (%) = 100 / (Contribution margin − Target profit rate).

Example: after product cost, shipping, payment fees and packaging, 35% of revenue is left on each order (contribution margin), and you want to keep 10% of revenue as profit after ads. Target ROAS = 100 / (0.35 − 0.10) = 400%. You enter 400 in Google Ads, meaning an average of $4 of conversion value for every $1 of ad spend.

Then run that number through three adjustments: returns, the gap to your historical ROAS (the starting value) and the target that maximizes profit. The sections below walk through each with examples.

What is the Target ROAS (tROAS) bid strategy and how does it work?

Target ROAS is Google Ads' value-based Smart Bidding strategy. At each auction it predicts the value of a potential conversion and bids to grow total conversion value while keeping the average conversion value / cost close to your target. It uses signals such as device, location, time of day and remarketing lists, bidding higher on searches that look valuable and lower on those that don't.

Two things to know. First, the target is an average: individual days or campaigns can land above or below it. Second, Google simplified strategy names in June 2026: 'Maximize conversion value with a Target ROAS' now shows simply as 'Target ROAS'; Google says bidding behavior did not change.

The strategy only makes sense if your account sends conversion values. Conversions with a value of 0 don't count, so first make sure the purchase tag passes the correct order value.

How many conversions does Target ROAS need?

Google Ads Help lists minimums by campaign type. Below these, you can still turn the strategy on, but the algorithm has little to learn from and results swing.

• Search and Shopping: at least 15 conversions in the past 30 days (at the conversion tracking level)
• Display: at least 15 conversions with values across campaigns in the past 30 days
• Demand Gen: 50 conversions in the past 35 days (10 in the last 7) or 100 across all Demand Gen campaigns in the account
• Video action campaigns: at least 30 conversions in the past 30 days
• Before setting a target: values reported for at least 4 weeks or 3 conversion cycles, whichever is longer

Step 1: Calculate target ROAS from contribution margin

Contribution margin = (Price − Product cost − Variable cost per order) / Price. Variable costs include shipping, payment fees, packaging and any marketplace commission. Using gross margin instead sets the target too low, so you can lose money while thinking you are profitable.

Break-even ROAS (%) = 100 / Contribution margin. At a 35% contribution margin, break-even is 286%; below that, ads lose money on every sale.

Target ROAS (%) = 100 / (Contribution margin − Target profit rate). The target profit rate is the share of revenue you want to keep after ad costs. Whether fixed costs (rent, salaries, software) belong in that rate is a business decision.

• 50% margin, 10% profit goal → 250% target ROAS
• 35% margin, 10% profit goal → 400% target ROAS
• 30% margin, 10% profit goal → 500% target ROAS
• 25% margin, 5% profit goal → 500% target ROAS
• 20% margin, 5% profit goal → ≈ 667% target ROAS

Step 2: Adjust the target for returns

Google Ads records conversion value when the order is placed; orders returned later stay in the reported value. In high-return categories such as apparel and footwear, platform ROAS looks noticeably better than real ROAS.

Approximate fix: Target ROAS to enter = Calculated target / (1 − Return rate). At 15% returns, 400% / 0.85 ≈ 470%; at 30% returns, 400% / 0.70 ≈ 571%. A cleaner route is to send returns back to Google Ads as conversion adjustments or to send different values by category, in which case this correction isn't needed.

Step 3: Pick a starting value based on historical ROAS

Even if your calculated target is right, don't enter it directly if it is far from what the campaign delivers today. Google recommends setting the target from business goals and past performance, and warns that an unrealistic starting target can lead to poor performance or limited scale.

To find historical ROAS, add the 'Conv. value / cost' column under Conversions and multiply by 100. Leave out the most recent days (your conversion lag); their conversions aren't complete yet.

Change the target in steps and wait 1–2 conversion cycles after each change (a conversion cycle is the typical time from click to purchase). Google doesn't specify a percentage; in practice we work with 10–15% steps.

• Historical ROAS 380%, target 470% → 380% → 420% → 470% (each step after 1–2 cycles). Jumping straight to 470% can cut spend sharply.
• Historical ROAS 560%, target 470% → 520% → 470%. Lowering the target enters more auctions and adds volume; watch whether ROAS slips below target.
• New campaign, no history → collect 2–4 weeks of data with Maximize conversion value (no target) or Target CPA, then move to Target ROAS.

Why doesn't the highest ROAS bring the most profit?

As you raise target ROAS, Google enters only the most valuable auctions: ROAS rises, but spend and sales fall. Past a certain point, the contribution lost from missed sales is larger than the ad spend saved. The table below is a hypothetical example for a store with a 35% contribution margin (illustrative amounts, not real account data).

Profit = Revenue × Contribution margin − Ad spend (contribution profit after ads, before fixed costs).

• Target 300% → spend $100,000, revenue $300,000, profit $5,000
• Target 400% → spend $60,000, revenue $240,000, profit $24,000
• Target 500% → spend $35,000, revenue $175,000, profit $26,250
• Target 600% → spend $20,000, revenue $120,000, profit $22,000

How do you find the right target with marginal ROAS?

Decide on marginal ROAS, not average ROAS: the return on the spend added or removed between two targets. Marginal ROAS = Revenue difference / Spend difference. If it is above break-even ROAS (here 100 / 35 ≈ 2.86), the extra spend is profitable.

In the example, going from 400% to 300% adds $40,000 of spend for $60,000 of revenue: marginal ROAS 1.5, far below break-even → loss. Going from 500% to 400% adds $25,000 for $65,000: 2.6, just below break-even → profit dips slightly. Going from 600% to 500% adds $15,000 for $55,000: about 3.67 → profitable. In this example the profit-maximizing target is 500%.

The formula's 400% is a 'grow as much as possible at 10% profit' decision; 500% is a 'maximize today's profit' decision. If new-customer acquisition and repeat purchases (LTV) matter to you, a lower target can be a deliberate choice. What matters is choosing it knowingly.

Should you send revenue or profit as conversion value?

The default setup sends order value (revenue). The algorithm then can't see margin differences: a $1,000 sale of a 60%-margin product and of a 15%-margin product look identical.

The alternative is to send contribution profit per order as conversion value (the POAS, profit on ad spend, approach). Break-even then becomes 100%: a 130% target means $0.30 of contribution profit per $1 of ad spend on average. It requires calculating product cost server-side or in the data layer; server-side tagging is preferred so product costs aren't exposed in the browser.

If a full setup isn't possible, split low-margin categories into separate campaigns with their own targets, or use conversion value rules to adjust value by location, device or audience segment.

Common Target ROAS problems and fixes

Most problems come from an unrealistic target, too little data or not waiting long enough after a change.

• Spend suddenly dropped → the target is far above historical ROAS. Lower it 10–15% and wait 1–2 cycles.
• ROAS stays below target → check conversion lag first (recent days look incomplete). If it persists, data is thin or the target too low; consolidate product groups or campaigns.
• Campaign is 'Limited by budget' with ROAS above target → profitable auctions are being missed. Raise the budget; if you can't, don't lower the target, because a lower target spends the same budget on lower-return clicks.
• The target changes daily → the algorithm readjusts every time. Review weekly.
• Separate ad group targets → Google doesn't recommend them; they limit Smart Bidding. Set targets at campaign or portfolio level.
• Short promotions (like Black Friday) → use a 1–7 day seasonality adjustment for the expected conversion-rate jump; it isn't recommended for periods over 14 days.

Target ROAS in Performance Max and Shopping

The same formula applies to Performance Max and Shopping; the difference is that products with different margins sit in one campaign. One target based on average margin subsidizes low-margin products. Grouping products by margin band with custom labels, then giving each group its own campaign and target, is the simplest way to pass margin information to the algorithm.

Google's bidding update from August 17, 2026 may cause temporary fluctuations, especially in budget-limited Target CPA and Target ROAS campaigns. Don't react to short-term swings in that period with immediate target changes.