Do the maths

Margin calculator

Before you spend a euro on ads, check how much you really keep from each sale. Change the values to match your product.

Selling price (what the customer pays)Product + supplier shippingCustoms and fees per parcelAds per sale (CPA)Reserve for returns and problemsFixed costs per monthPrice includes 21% VAT (if you are registered in Spain, it does)

Payment fee included: 2.1% + €0.30 (card via Shopify Payments, Basic plan).

Selling priceWhat the customer pays, VAT included if you are registered in Spain.

Product + shippingWhat the supplier charges you for the product delivered to the customer.

Customs and feesFor parcels from outside the EU: €3 per type of item since July 2026 and a planned handling fee per parcel. Enter 0 if your supplier is in the EU.

Ads per sale (CPA)What it costs you in ads to get one sale. When you start it’s usually between €10 and €30, or more.

Returns and problemsMoney you set aside on each sale for refunds and products that arrive damaged.

Fixed costsShopify, apps, domain and self-employed contribution: you pay it every month, whether you sell or not.

Don’t understand a result? It’s all explained in the lesson The numbers of a sale.