Ethereum gas fees change based on supply and demand on the network. Since Ethereum can only handle a certain number of transactions per block, users compete to get theirs processed. People offer higher fees, and validators choose to process the transactions that pay more first.
Another reason Ethereum gas fees change is the network’s built-in fee system. If blocks are more than half full, the network automatically raises the base ETH gas fee, and vice versa. This adjustment happens with every block (about every 12 seconds) so gas fees can change quickly, even if you don’t do anything different.
ETH gas prices also depend on the type of transaction. Simple actions like sending or trading ETH have low gas fees. Swapping tokens on a decentralized exchange (DEX) needs more computing power, so the fee is higher. Minting NFTs or doing complex DeFi actions uses even more power, so these have the highest gas prices.
You can also add a tip, called a priority fee, to speed up your Ethereum transaction. A low tip makes your transaction cheaper but slower. A high tip costs more but gets processed faster. If many people add high tips, the average fee goes up for everyone.