Gas Fee

A gas fee is the payment a blockchain network charges to process a transaction — it compensates the validators or miners who include your transaction in a block, and it exists independently of any exchange or wallet you're using.

Every action on a network like Ethereum, from a simple transfer to a complex smart contract interaction, consumes computational resources, and gas is how that consumption is priced and paid for. Fees fluctuate with network demand: during periods of high activity, more people are competing for limited block space, and gas prices rise; during quiet periods, they fall. This is why the same type of transaction can cost a few cents one day and several dollars the next on a busy network.

It's important to distinguish a gas fee from an exchange's own pricing. When you swap crypto, you're typically paying two separate things: the network's gas fee to move your deposit and, later, your withdrawal on-chain, and the exchange partner's spread baked into the quoted rate. Gas goes to the network, not to the exchange — no platform can eliminate it, since it's a cost of using the blockchain itself, though some networks are simply cheaper than others by design.

This is a real, practical consideration when choosing which network to use for a swap on Zest: many assets are available across multiple networks (for example, USDT on Ethereum versus a lower-fee network), and picking a cheaper network can matter more than the swap rate itself for smaller amounts, where gas could otherwise eat a large share of the value moved. Zest's Ethereum gas fee tracker, at /tools/eth-gas, shows live estimated fees so you can gauge whether it's a good time to transact on Ethereum mainnet or whether routing through a cheaper option makes more sense.

One major reason gas fees have come down for many use cases is the rise of Layer 2 networks, which handle transactions more cheaply while still settling back to a base chain like Ethereum. Gas is also directly tied to how quickly and reliably your deposit gets picked up for network confirmation — if you set a gas price too low during a busy period, a transaction can sit unconfirmed for a long time. And if you're moving assets across chains rather than within one, a bridge typically involves gas costs on both the source and destination networks, which is worth budgeting for before you start.