How to work out your marketing budget in 4 steps
1. Find what one sale leaves you. Price, minus what the product costs you with shipping, minus about 3% in payment fees. A $120 product that costs you $40 leaves about $76. That's the most you can pay to get a customer. Aim for about two-thirds, $51, so a third of every sale stays as profit.
2. Work out what a customer costs you. You pay for clicks, but only some visitors buy.
Cost per customer = cost per click ÷ conversion rate
At $1 a click and a 1% conversion rate you pay for 100 clicks to get one buyer: $100. That's more than the $76 a sale leaves you.
3. Find the conversion rate you need. Cost per click ÷ what you can pay: $1 ÷ $76 = 1.3% to break even, $1 ÷ $51 = 2% to keep a healthy profit.
4. Multiply out the budget.
Marketing budget = sales you want ÷ conversion rate × cost per click
| Visitors for 300 sales at 1% | 300 ÷ 1% | 30,000 |
| Budget at $1 a click | 30,000 × $1 | $30,000 / month |
| Profit at 1% | 300 × ($76.40 − $100) | −$7,080 / month |
| Budget at 2% conversion | 15,000 × $1 | $15,000 / month |
| Profit at 2% | 300 × ($76.40 − $50) | $7,920 / month |
Same product, same ads, same 300 sales. Going from 1% to 2% conversion turns a $7,080 monthly loss into a $7,920 profit, on half the budget. Profit here is before your other costs: team, apps, rent. To see every cost line, use the Shopify profit calculator.
What about LTV (repeat orders)?
Some customers come back. If an average customer orders 1.5 times in a year, they leave you 1.5 × $76 = $115 before ads, not $76. That's their lifetime value (LTV), and it's the most you could pay for them over a year.
Most you can pay over 12 months = what one sale leaves × orders per customer
At $1 a click and 1% conversion, a $100 customer loses $24 on the first order and earns it back on the repeat order: about $4,380 profit over the year from 300 customers. That works only if they really come back, and you pay for the ads today while repeat orders come months later. That's why the calculator shows both: profit on first orders (your cash now) and profit with repeat orders (the year).
Be careful: your industry may cost more
A common range for online stores selling through Meta, Google and TikTok is a customer cost of 30–40% of the price. Many industries pay more: expensive products, competitive niches like beauty or supplements, and anything people think about for weeks before they buy. Clicks cost more there too. Start with $1 and 1% if you have no data, then replace them with your real numbers from your ad account and store analytics after the first weeks.
If the cost per customer is more than one sale leaves you, ads lose money at this price. Raise the conversion rate, raise the price, or sell more per order. The product pricing calculator shows the price you need.
Marketing budget as a percentage of revenue
The classic advice is 7–10% of revenue. That fits a shop where customers walk in. An online store that sells through ads usually spends 15–35%, because ads are its shop window. Start from your own price, click cost and conversion rate, not a percentage.
The cheapest way to get customers for less
Doubling your conversion rate halves what every customer costs, with the same ads. That's why the best-run brands improve and A/B test the pages their ads land on before they spend more.