According to the ZVPot (the Consumer Protection Act) , the consumer has the right to return the goods without giving the retailer a reason, even if the purchase was made online. In such circumstances, the customers bears the costs of returning the goods.
In particular, in the case of distance contracts and consequently online purchases, the customer has 14 days to inform the merchant that s/he is withdrawing from the contract. The withdrawal period shall be deemed to begin on the day on which the consumer receives the goods, and for online purchases the day of conclusion of the contract.