Welcome to the NZRT Wiki Podcast. Today we’re looking at Gas & Transactions.

If you’ve ever sent a transaction on a blockchain network, you’ve encountered gas. Gas is the unit that measures how much computational work a transaction requires. Every on-chain operation you perform consumes gas, and you pay for it in ETH. The good news, especially if you’re working on Base, is that gas fees there are remarkably cheap — we’re talking around one cent per transaction. Compare that to Ethereum’s main layer, where you might pay anywhere from five to fifty dollars or more for the same operation. So the network you choose really does matter.

Let’s break down what actually makes up a transaction. Think of a transaction as a small packet of information sent to the blockchain. It has seven key fields. First, there’s the from field — that’s the sender’s address, identifying who is initiating the transaction. Next is the to field, the recipient’s address, which could be another person’s wallet or a smart contract. Then there’s the value field, holding the amount of ETH you’re sending, measured in a very small unit called Wei. After that comes the data field, used when you’re calling a function on a smart contract — it holds the encoded version of that function call. Then you have the gas field, which sets the gas limit, essentially the maximum amount of gas you’re willing to let the transaction use. Next is the gas price field — under the modern fee model this is called max fee per gas — and it tells the network how much you’re willing to pay per unit of gas, measured in Gwei. Finally, there’s the nonce, a sequential counter that tracks how many transactions a particular address has sent, helping prevent duplicates from being processed.

So how do you calculate what you’ll actually pay? The formula is straightforward. Your transaction fee equals the amount of gas used, multiplied by the gas price. If you know those two numbers, you can work out the cost.

To give you a feel for what that means in practice, let’s look at a few examples on Base. A simple ETH transfer uses around twenty-one thousand gas units. At a gas price of about zero-point-zero-zero-one Gwei, that works out to roughly a fraction of a cent. An ERC-20 token transfer is a bit more involved, using around sixty-five thousand gas units. And if you’re deploying a full smart contract, you’re looking at anywhere from five hundred thousand to two million gas units, depending on how complex the contract is.

Now, there’s a specific fee model worth understanding, called EIP-1559, which arrived with what’s known as the London upgrade to Ethereum. Before this change, gas pricing was a simple open auction. After the upgrade, fees split into two parts. There’s a base fee, set automatically by the network based on how busy it is — and this portion is actually burned, meaning it’s permanently removed from circulation. Then there’s a priority fee, sometimes called a tip, which goes directly to the validator who processes your transaction. The maximum fee you set covers both of these. In practice, this model makes fees more predictable because the base fee adjusts up and down with network demand rather than spiking unpredictably.

When you’re configuring a development environment — say, with a tool like Hardhat — you can set the gas price to auto, which lets the tool determine the appropriate value for you automatically. Or you can specify an exact value in Wei if you need precise control over your costs.

If you’re working on a test network and need some ETH to experiment with, there are a few places to get it for free. For Base Sepolia, the test version of the Base network, you can visit the Coinbase faucets page or Sepolia Faucet dot com. Alchemy also runs a faucet, though that one requires you to have an Alchemy account set up first. These faucets drip small amounts of test ETH into your wallet so you can practice without touching real funds.

To go deeper on what we covered today, check out the related wiki pages on Ethereum and the Base Network, and on Contract Deployment, which gets into what happens when you push a smart contract to the chain and why those gas costs are so much higher than a simple transfer.

That’s it for this episode of the NZRT Wiki Podcast. Thanks for listening.