What free shipping actually costs your order

Compare the seller’s cost with what the buyer pays.

Buyer-paid shipping is revenue; the shipping bill you pay is an expense. Keep them in separate fields. Entering the same number in both does not mean shipping has no effect when percentage fees also apply to collected shipping.

In our sample, product revenue is $50 and buyer shipping is $5. Contribution is $20.05 after all entered variable expenses. If you keep the product price at $50 and offer free shipping, contribution falls to $15.20: you lose $5 of revenue but pay $0.15 less in percentage fees.

To keep total revenue unchanged, raising the product price to $55 and setting buyer shipping to zero restores the original contribution in this simplified model. That does not mean customers will buy at the same rate; this tool calculates unit economics, not demand.

Save the original and free-shipping scenarios side by side. Keep your shipping expense in both. Taxes, regional shipping differences and platform-specific fee exemptions require their own treatment.