Enter your ad spend
What you paid the platform for the campaign or ad set you want to judge.
Add your revenue
The total sales value the platform attributes to that campaign over the same window.
Add your costs (COGS)
What the product or service actually costs you. This unlocks real ROI and net profit.
Step 1 — Ad spend
This is the simplest of the three and the only one nobody argues about: the amount the advertising platform billed you. Take it straight from the "Amount spent" column in Meta Ads Manager, "Cost" in Google Ads, or "Cost" in TikTok Ads Manager.
Two things to watch. First, pick a level and stay there — if you take spend from one campaign, take revenue from the same campaign, not from the whole account. Second, if an agency or a freelancer charges you a percentage of spend, add that fee here; it is a real cost of running the ad.
Step 2 — Revenue
The total sales value attributed to that campaign in the same date range. In Meta this is "Purchases conversion value"; in Google Ads it is "Conv. value"; in TikTok, "Total complete payment value".
Use revenue net of sales tax or VAT. That money was collected on behalf of the tax authority and was never yours, so including it inflates every metric on the page. If your store reports gross figures, divide by 1 + your tax rate first — €12,100 including 21% VAT is €10,000 of real revenue.
If refunds are meaningful in your business, subtract the expected refund rate here rather than pretending it will not happen. A 3× ROAS with 20% returns is really a 2.4× ROAS.
Step 3 — Cost of goods (COGS)
This is the field most people leave empty, and it is the one that turns a vanity metric into a business metric. Include every variable cost tied to fulfilling those specific orders:
- the product itself — manufacturing or wholesale cost;
- packaging and inserts;
- shipping and fulfilment, including what you subsidise on free delivery;
- payment processing (roughly 2–3% plus a fixed fee per transaction);
- the cost of expected returns and replacements.
Leave out fixed costs — rent, salaries, software subscriptions, your agency retainer. Those do not scale with the next order, so they belong in your monthly profit-and-loss statement, not in a per-campaign calculation. Mixing them in makes every campaign look unprofitable and tells you nothing useful.
Selling a service or software with no unit cost? Leave COGS at zero. ROI and ROAS then converge, which is correct: with no cost of delivery, every euro of revenue above your ad spend is profit.
Reading the result
The results update as you type — there is no calculate button. Four numbers appear:
| Metric | Reads as | What it tells you |
|---|---|---|
| ROAS | A multiple, e.g. 3.60× | How hard the ad platform is working |
| Net profit | Currency | What actually stayed in the business |
| ROI | A percentage | The return on everything you put in |
| Break-even ROAS | A multiple | The line you must stay above |
The colour is the fastest read of all: green means the campaign is making money, red means it is losing it, amber means you are sitting exactly on break-even. Below them, the gauge shows how far above or below that break-even line you are, and a secondary strip gives gross margin, ACOS, profit margin and total cost.
Sharing and re-using a calculation
"Copy results" puts a plain-text summary on your clipboard, ready for Slack or an email. "Copy link" encodes the three figures into the URL itself, so sending that link to a colleague opens the calculator with your exact numbers already filled in. Nothing is uploaded in either case — the figures travel inside the link, not through a server.