What is the transaction fee market?
- Author
- CRYPTO PORT Editorial
- Published
- Updated
- Reading time
- 4 min
In short
The fee market is the auction users run for limited block space. Fees are paid for the size or computation a transaction consumes, not for the amount being sent. When blocks fill, the highest bids go first, so anything that can wait is cheaper sent during a quiet period.
Key points
- An auction for scarce block space
- Priced by size or computation, not by the amount sent
- When busy, the highest bids are included first
- Sending during quiet periods costs less
Definition
The mechanism by which, because block space is capped, the fee a user offers determines how quickly their transaction is included.
The amount of transaction data a block can carry is capped — by weight on Bitcoin, by a gas limit on Ethereum. When more people want that space than there is space, the producer selects the highest bidders, and an auction forms in practice.
The key point is that fees are unrelated to the amount you send. Bitcoin charges per byte, Ethereum per unit of gas. Consolidating many small UTXOs or calling a complex contract can therefore cost a great deal even when the value moved is tiny.
Fee levels rise and fall with demand. Sending in a quiet window is cheap; sending during a rush is not. Wallets suggest a rate from current conditions, but that suggestion is a forecast and guarantees nothing about when you will actually be included.
Watch out for
- · Set the fee far too low and the transaction can sit pending for days or be dropped entirely
- · A wallet's suggested fee is an estimate, not a promise about confirmation time
- · Absolute fee levels change daily, so do not budget from a figure you saw before