Gas Fees
Every action on a blockchain — transferring a token, interacting with a smart contract, minting an NFT — requires computation. On networks like Ethereum, that computation is measured in units called gas. Gas is not a fixed dollar amount; the total fee depends on two things: how much gas the action requires (its gas limit, reflecting complexity) and the gas price users are willing to pay per unit, typically quoted in gwei (one gwei equals one-billionth of one Ether).
Gas prices fluctuate with network demand, much like surge pricing on a ride-hailing app. When many users are competing to have their transactions confirmed quickly, they bid up the gas price. During quiet periods, fees fall. Suppose a simple token transfer costs 21,000 gas units. If the gas price is 20 gwei, the fee is 21,000 × 20 gwei = 420,000 gwei, which equals 0.00042 Ether — worth more or less depending on Ether's price at the time. This is a hypothetical illustration of the mechanics, not a current or guaranteed cost.
Gas fees are a meaningful part of the economics of DeFi activity: high fees can make small transactions economically impractical, pushing activity toward Layer 2 networks — secondary systems built on top of a main blockchain to process transactions more cheaply. Understanding gas helps explain why on-chain activity tends to cluster during low-fee windows. Live crypto data is available on /crypto.