ROAS

Return on ad spend (ROAS) is the conversion value an ad platform attributes to your ads divided by the cost of those ads. In Google Ads the same idea appears as the Conv. value / cost column, which Google defines as conversion value divided by cost and describes as an estimate of return on investment. A ROAS of 4 means $4 of attributed revenue per $1 of ad spend. Google writes the same thing as a percentage when you set a Target ROAS: $5 of sales per $1 of spend is a 500 percent target. In Google Ads you can add the Conv. value / cost column next to Cost and Conv. value. The three columns together let you check the arithmetic and spot a campaign where a few unusually large orders carry the average.

ROAS depends entirely on what goes in the top line. Google's conversion values page says you can assign the same value to every conversion or a different value to each, and that values feed the Conv. value / cost column and bid strategies like Target ROAS and Maximize conversion value. If your tag sends the wrong amount, or leaves out tax and shipping inconsistently, ROAS is wrong from the start. Attribution also decides which sales count: windows, models, and view-through credit all change the number. The same campaign can show different ROAS in Google Ads, GA4, and Meta. Windows affect the number. A campaign judged on the last three days will look worse than it is, because Google advises excluding the most recent conversion delay period, the time between a click and the conversion being recorded.

ROAS interacts with bidding. Target ROAS is a Smart Bidding strategy where Google predicts the value of each potential conversion and sets bids so the average return approaches your target. Google lists requirements by campaign type, such as at least 15 conversions in the past 30 days for Search and Shopping, and says a target set too high may limit the traffic your ads get. It also suggests excluding the most recent conversion delay period when you evaluate ROAS. Expect one to two conversion cycles for a new target to settle. For lead businesses, ROAS needs a lead value. A fixed value of $100 per lead makes ROAS a restatement of cost per lead, while assigning values based on close rate and job size makes it informative.

ROAS ignores margin, shipping, returns, fulfillment, and fixed costs. A ROAS of 3 can be profitable at a 60 percent margin and a loss at a 25 percent margin. It also cannot say whether the buyer would have purchased anyway, which matters most on branded search and retargeting. Frequent mistakes: comparing ROAS across channels with different attribution, treating a platform figure as proof of profit, setting a target without looking at your history first, and judging a campaign on a few days when conversions lag the clicks. Branded search and retargeting often show the best ROAS because they capture people already close to buying. That high number does not mean the budget should move there, since it may add little beyond what would have happened.

To use it this week, find your break-even ROAS from your margin, then sort campaigns by ROAS against that line for a window that excludes the last few days of conversion delay. Add the Conv. value / cost column next to cost and conversion value so you can see the pieces. Check that the conversion value your tag sends matches your real order totals. If a campaign has a great ROAS but small volume, the question is whether it can scale, not whether it is good. Use ROAS next to volume. A 6.0 return on $200 a month and a 3.0 return on $5,000 a month describe different decisions, and the second may bring more profit.