Sources we use
We use primary sources only: ad platforms’ own help centers and billing documentation (Google Ads, Microsoft Advertising, Meta Business Help Center, Google Analytics, YouTube), industry measurement standards (IAB and MRC guidelines, AMEC’s Barcelona Principles), U.S. government publications (Federal Trade Commission, U.S. Census Bureau), peer-reviewed marketing research and open textbooks (OpenStax), and public companies’ filings with the SEC. Agency blogs, vendor “benchmark reports” and listicles are never used as sources of fact, and we do not publish industry average CTR, CPC or ROAS figures we cannot trace to a published, dated source.
How calculators are checked
Every calculator uses published, standard formulas. The code is covered by automated tests that check known answers (for example, $500 of ad spend for 125,000 impressions is a $4.00 CPM, and $2,000 of revenue on that spend is a 4x ROAS; our tests check these and dozens of other hand-worked answers). We show the formula next to each tool so anyone can verify the result by hand.
What we will not publish
- Affiliate links, sponsored tool rankings, agency referrals or lead forms.
- Untraceable “industry average” CTR, CPC, conversion-rate or ROAS figures presented as fact.
- Claims we cannot support with a source.
Updates and corrections
Each page shows the date it was last updated. Ad platforms change how they define, count and bill metrics through the year. We re-check the linked documentation when we update a page, re-run the tests, and change page dates only when content changes. If you find an error, tell us through the contact page and we will review it and correct it.