The gemini has a comparatively simple fee structure which often works out significantly cheaper than a regular Coinbase account. The fees are calculated using your trading volume, which is determined by how much you have traded over the previous 30 days as well as shown in US dollars.
When you place a cryptocurrency order at the market price which gets filled immediately, a taker fee applies. On the other hand, a “maker fee” applies when you place an order which is not immediately matched by an existing order. Due to this, your order gets placed on an order book.
If another customer places an order that matches yours, you are then considered the maker. When you place an order that is partially matched, you pay a taker fee for that portion while the remainder is placed on the order book and is considered as a maker order.