Business and Financial Tools
ROAS and Break-even Advertising Budget Calculator
Compare revenue per ad-spend unit with what remains after variable and additional costs.
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ROAS and Break-even Ad Budget Calculator
Use matching periods and see what remains after costs.
From your entered data
Ad economics
High ROAS does not prove profitability. The maximum-budget scenario holds revenue and margin fixed; it is not a recommendation to increase actual spend.
Where the revenue goes
| Item | Amount |
|---|
Period-based model: ROAS = entered revenue / ad spend. Scenario profit = revenue × contribution margin − ad spend − additional costs. Does not establish causal attribution or include tax, returns, unentered costs or lifetime value. Break-even ratios are rounded for display; use the break-even revenue amount to check the threshold. No advertising accounts are connected or modified.
Quick answer
What ROAS reaches break-even under my cost assumptions?
ROAS is entered ad-attributed revenue divided by ad spend. Profit also depends on contribution margin: scenario profit = revenue × margin before ads − ad spend − additional costs. Approximate break-even revenue divides ad spend plus additional costs by contribution margin.
How to use this tool
- Enter same-period ad spend and attributed revenue. Defaults are illustrative.
- Enter margin remaining after variable costs, before ads and the additional costs entered separately. Avoid double-counting.
- Enter additional fixed costs and same-period order count, then calculate.
- Review profit alongside ROAS and break-even revenue. Export Print, Excel, PDF or TXT.
How the calculation works
Use the same period and currency. Contribution rounds half-up to satang from revenue times contribution margin. Scenario profit subtracts ads and additional fixed costs. Maximum ad budget is contribution minus additional costs, assuming unchanged revenue and margin. Break-even revenue is (ad spend + additional costs) / contribution margin, rounded upward to satang. ROAS displays a multiple; scenario profit/ad spend displays percent. Order averages use the entered whole order count.
Examples
| Example | Input | Expected result |
|---|---|---|
| 5× ROAS still needs a cost check | |
ROAS 5.00×; contribution THB 20,000; scenario profit 5,000; profit/ad spend 50%; approximate break-even revenue THB 37,500. |
| High ROAS, negative profit | |
ROAS remains 5×; scenario loss THB 5,000; break-even revenue estimate THB 75,000. |
| Zero spend or orders | |
ROAS and profit/ad spend are undefined at zero spend; order averages are undefined at zero orders. |
Limitations
- Does not prove causal attribution, correct cross-channel double counting, or include tax, refunds, lifetime value or unentered costs.
- Results depend on same-period margin and costs without double-counting.
- Money: THB 0–100,000,000 per input; margin: 0–100%, up to two decimals; orders: whole 0–1,000,000. Uses integer satang.
- Break-even revenue rounds upward; displayed ratios round to two decimals. Zero margin with costs has no defined threshold. No maximum budget is shown if contribution cannot cover additional fixed costs.
Frequently asked questions
Does 5× ROAS mean five times the profit?
It means entered revenue is five times ad spend, equivalent to 500% ROAS. Profit still requires a cost calculation.
Where does contribution margin come from?
Subtract variable product costs, fees and shipping from revenue, then divide by revenue before ads and the separately entered fixed costs. The seller-profit tool can help check per-order assumptions.
Is the maximum budget a recommendation to spend more?
It is only the budget that reaches zero modeled profit while holding revenue and margin fixed. It does not predict revenue after changing spend.
Does this connect to advertising accounts?
No. It neither tracks nor modifies campaigns. Calculations use locally entered data only.
References
- Google Ads — ROAS และมูลค่า Conversion / ROAS and conversion value Verified 2026-10-06
- Google Ads — มูลค่าของ Conversion / About conversion values Verified 2026-10-06
Content and calculation method last reviewed: