As an author or publisher, you can decide how much you want to charge for your audio book. There is no fixed price and you can offer your audiobook at different prices in different stores.
With Audible, for example, you only have to specify a suggested retail price, but Audible usually sets the price itself. Audible will usually take the author's suggested price into account, but may offer the audiobook at a lower price if it is part of their subscription model.

In general, the price depends on the length of the audiobook.
For audio books

• less than one hour, the price is less than €6.95


• between 1 and 3 hours between €6.95 and €9.95


• between 3 and 5 hours between €9.95 and €19.95


• between 5 and 10 hours between €14.95 and €24.95


• between 10 and 20 hours between €19.95 and €29.95


• more than 20 hours: between €24.95 and €34.95

It is important that your audio book has a reasonable price that reflects the value of your work. So do not hesitate to ask for a higher price.