Blended ROAS Calculator
Add up what Google, Meta, and TikTok each claim they generated, compare it with what your store actually recorded, and see your real blended ROAS across every channel.
Enter your numbers
Ad channels
Actual store revenue
Your result
Blended ROAS
3.00x
Actual store revenue ÷ total spend across all channels
Sum of platform-reported revenue
$17,500.00
Actual store revenue
$12,000.00
Inflation gap
$5,500.00 (45.8%)
Total spend across channels
$4,000.00
Platforms are claiming $5,500.00 more revenue than your store actually recorded. Several channels are likely taking credit for the same order. Use blended ROAS, not platform ROAS, when deciding what to scale.
Average self-reported platform ROAS: 4.38x vs. blended ROAS of 3.00x
Why this happens
Each platform attributes a sale to itself whenever it can find a touchpoint, even if another channel also touched the same order. Summing self-reported revenue across Google, Meta, and TikTok almost always double-counts purchases. Blended ROAS, anchored to your store's actual revenue, removes that overlap.
Want your blended ROAS to stay current?
Daymark connects your store and ad platforms to monitor blended ROAS, revenue, and spend as your channel mix changes.
Track this with live data →What Is Blended ROAS?
Blended ROAS is your total store revenue divided by your total ad spend across every channel combined.
Blended ROAS = Actual Store Revenue / Total Ad Spend (All Channels)
If you spend $2,000 on Google Ads, $1,500 on Meta Ads, and $500 on TikTok Ads, your total spend is $4,000. If your store actually recorded $12,000 in revenue over that period, your blended ROAS is 3.0x. That number comes from one revenue source, your order system, not from adding up what each ad platform separately claims it generated.
Why Blended ROAS Is Different From Platform ROAS
Each ad platform reports its own ROAS using its own attribution. Google Ads counts a sale if it sees a touchpoint in its own conversion path. Meta does the same inside its network. TikTok does the same inside its network. None of them can see what happened on the other two.
That means a single order can get counted as a conversion by Google, by Meta, and by TikTok at the same time. Add up their self-reported revenue and you are not looking at three separate pools of sales. You are looking at the same sales claimed multiple times.
This calculator adds up what every platform reports, then compares that sum with what your store actually recorded for the same period. The difference is the inflation gap. It is not extra revenue. It is double-counted revenue.
How This Calculator Works
Enter spend and platform-reported revenue for each ad channel (Google Ads, Meta Ads, TikTok Ads, or any others you run), plus your actual total store revenue for the same period, such as Shopify net revenue.
The calculator returns:
- the sum of platform-reported revenue across all channels
- your actual store revenue
- the inflation gap between those two numbers, in dollars and percent
- blended ROAS, calculated as actual store revenue divided by total spend across all channels
Blended ROAS is the number to use when deciding whether your overall paid acquisition is working. Platform ROAS is still useful for comparing channels against each other, but it should never be summed across channels to estimate total return.
What Your Results Mean
| Result | What it means |
|---|---|
| Inflation gap is small | Platforms have little overlap right now; channel-level ROAS is a fair proxy for blended ROAS |
| Inflation gap is 10-25% | Some real attribution overlap; check which channel is overclaiming before trusting its standalone ROAS |
| Inflation gap is above 25% | Heavy double-counting; platform-reported ROAS is not a reliable basis for budget decisions |
| Blended ROAS is below your break-even ROAS | Combined paid spend is not covering order costs, even if individual platforms look profitable |
A campaign dashboard showing 5x on Google and 4x on Meta does not mean your combined return is somewhere around 4.5x. If both platforms are claiming the same orders, your actual blended ROAS could be closer to 2.5x once the overlap is removed.
Example: The Gap Between Reported and Actual Revenue
| Channel | Spend | Platform-Reported Revenue |
|---|---|---|
| Google Ads | $2,000 | $9,000 |
| Meta Ads | $1,500 | $6,500 |
| TikTok Ads | $500 | $2,000 |
| Total | $4,000 | $17,500 |
Actual store revenue for the same period: $12,000
Sum of platform-reported revenue ($17,500) is well above actual store revenue ($12,000), an inflation gap of $5,500, or about 46%. Blended ROAS is $12,000 ÷ $4,000 = 3.0x, not the 4.4x average you would get by naively averaging each platform's self-reported number.
Common Mistakes With Multi-Channel ROAS
- Adding up each platform's reported ROAS or revenue to estimate total return
- Scaling the channel with the highest self-reported ROAS without checking it against store revenue
- Treating platform dashboards as the source of truth for total revenue
- Ignoring the inflation gap until it grows large enough to distort budget decisions
- Comparing blended ROAS across stores without confirming both used actual order revenue, not platform-reported revenue
Frequently asked questions
What is blended ROAS?
Blended ROAS is total store revenue divided by total ad spend across every channel combined. Unlike platform-reported ROAS, it uses one revenue number from your order system, not each platform's self-attributed figure, so it cannot be inflated by overlapping attribution.
Why is blended ROAS lower than the ROAS shown in each ad platform?
Each ad platform attributes a sale to itself whenever it detects a touchpoint, even if the customer also clicked an ad on another channel first. Summing Google, Meta, and TikTok's self-reported revenue almost always double-counts orders, which makes platform ROAS look higher than what the store actually earned.
How do you calculate blended ROAS?
Blended ROAS = Actual Store Revenue ÷ Total Ad Spend Across All Channels. Add up what you spent on Google, Meta, TikTok, and any other paid channel, then divide your store's actual revenue for that period, such as Shopify net revenue, by that total.
Why do Google Ads and Meta Ads both claim credit for the same sale?
Most platforms use last-touch or assisted-conversion attribution within their own ad network, so they count a sale if their ads were anywhere in the path. They have no visibility into what happened on a competing platform, so two or three channels can each report the same order as their own conversion.
What is a good blended ROAS for ecommerce?
There is no universal target. Use your break-even ROAS, based on contribution margin, as the floor for blended ROAS rather than an industry benchmark. A blended ROAS above that floor means your combined ad spend is covering variable order costs across every channel together.
Should I trust Shopify revenue or ad platform revenue for ROAS?
Use your store's order system, such as Shopify, as the source of truth for revenue. It records what was actually paid for, once, regardless of how many ad platforms claim a touchpoint. Ad platform revenue is useful for channel-level optimization, but not for measuring total return on ad spend.
How big is the gap between platform-reported and actual revenue usually?
The gap varies by business, but it is rarely zero once more than one paid channel is running. A 15 to 30 percent inflation gap between summed platform revenue and actual store revenue is common for stores running Google, Meta, and TikTok ads at the same time.
More Free Tools for You
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Break-Even ROAS Calculator
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Ecommerce Contribution Margin Calculator
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Track blended ROAS with live store and ad data
Daymark connects Shopify, Google Ads, Meta Ads, and TikTok Ads so blended ROAS, margin, and CAC stay grounded in what your store actually recorded.