How it's worked out
order value × (1 − returns) − product cost − shipping − fees. It's what's left to pay for ads and profit.
1 ÷ contribution margin. Below this, every sale from ads loses money. Target ROAS is 1 ÷ (margin − profit wanted).
If customers buy again, you can run below break-even on the first order and still win. Check that with the LTV calculator before you cut spend.
Leaves out fixed costs like staff and rent, so treat break-even as the floor, not the goal.
Shopify, GA4 and Meta all show different revenue?
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