When you send an Ethereum transaction, you specify your gas price, typically denominated in Gwei, and a gas limit. The gas price you set determines how much you’re willing to pay per unit of gas. Whereas, the gas limit determines how many units of gas you’re willing to pay for. You can think of your gas limit like a budget you set for the miner processing your transaction.
Gas markets determine if and when transactions will get confirmed. Set your gas price too low and your transaction may get stuck. But, set your gas limit too low and your transaction cannot be executed because it runs out of gas.
Most of the time, your wallet automatically fills in the gas limit for you. Simple transfers typically require a limit of 21,000 units. Whereas complex interactions with What are smart contracts? A smart contract is a computer pro... More can require a limit of 100,000 or even 200,000. A general rule of thumb is that the more complex the transaction, the higher the gas limit will need to be. So don’t try and save gas by lowering your limit because it won’t change the amount of resources needed to process your transaction. Your transaction will just run out of gas and you’ll have to resubmit it, costing you more in gas fees.