Pay what you can

Pay what you can (PWYC) is a non-profit or for-profit business model which does not depend on set prices for its goods, but instead asks customers to pay what they feel the product or service is worth to them. It is often used as a promotional tactic, but can also be the regular method of doing business. It is a variation on the gift economy and cross-subsidization, in that it depends on reciprocity and trust to succeed.

"Pay what you want" is sometimes used synonymously, but "pay what you can" is often more oriented to charity or socially oriented uses, based more on ability to pay, while "pay what you want" is often more broadly oriented to perceived value in combination with willingness and ability to pay.

Giving buyers the ability and freedom to decide what they are willing to pay for can be very successful, this eliminates the issues of conservative pricing. Buyers are attracted to the fact they are not obligated to pay a certain price for a product, this eliminates all issues of an item becoming overpriced in the consumers eyes, the customer can then make their own judgement on what the product is actually worth.

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Wikipedia