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Tag the link before you spend the budget
A campaign you cannot attribute is a campaign you cannot judge, and the tagging has to happen before the traffic arrives, not after. The UTM builder lower-cases and hyphenates values so one campaign stays one campaign in your reports instead of splitting into three.
The number most people skip
ROAS does not know your margin
Return on ad spend is measured on revenue, so it says nothing about whether the campaign made money. The threshold that does is your break-even ROAS, and it falls straight out of your gross margin: at a 40% margin you need a ROAS of 2.5 before the first unit of profit appears.
An identity worth keeping
CPM, CPC, and CTR are one number in three costumes
Fix any two and the third is decided: CPC equals CPM divided by CTR times ten. The CPM, CPC and CTR tool shows all three at once, which makes it obvious when a platform report is quoting a different denominator than you assumed.
No industry averages
We do not publish numbers we cannot source
Marketing sites are full of confident claims about what a good CTR or a normal conversion rate is. We have no sourced figures for those, so we print none — the reference chart here contains only cells derived from a formula. An automated test fails the build if that kind of claim appears in the copy.
Where the money leaks
The worst step is not the lowest rate
A funnel step with a 16% pass rate can be less urgent than one at 25%, because what matters is the headcount lost, not the percentage. The funnel calculator ranks the steps by people lost so the biggest leak is the one you see first.
Nothing is stored
Your spend figures stay in the tab
These tools ask for ad spend, revenue, customer counts, and list size — commercially sensitive numbers, all of them. There is no account, no server call, and no database. The maths runs in your browser and the privacy policy sets out exactly what that means.