Return on ad spend, or ROAS, tells you how much revenue you earn for each unit of ad spend. It is a helpful number, but only when your tracking is accurate and you read it in context.
Start with the tracking
Check that purchases are recorded once, with the right values, and that your ad platform and your store broadly agree. If they do not, fix that before you change anything else. No amount of optimisation can correct broken attribution.
Know that platforms report generously
Each ad platform credits itself for sales it influenced, so totals across platforms often add up to more than you actually sold. Compare platform numbers with your store's own revenue to keep yourself honest.
Look beyond a single number
A high ROAS on a small budget may not hold when you scale. Watch how results change as spend rises, and look at new-customer revenue as well as total revenue.
Connect ROAS to profit
Your break-even ROAS depends on your margins, shipping and fees. Work it out so you know which results make money and which only look good.
Test one thing at a time
Change creative, audiences or offers in a controlled way so you know what made the difference. Give tests enough time and budget to be meaningful.
Scale gradually
Raise budgets in steps and watch the effect. If results hold, keep going. If they slip, you will know exactly where.
