How Ethereum Gas Works: Gwei, Base Fees, and EIP-1559

Ethereum gas works like a pricing system where every action on the network has a cost, and you pay more when the network is busy and less when it’s quiet. The fee is calculated based on how much work your transaction needs and current demand.

But behind this simple idea is a system that many people find confusing at first. Terms like gwei, gas limits, and base fees often come up, especially after EIP-1559 changed how fees are calculated. To really understand how Ethereum gas works and what you’re paying for, we need to break down how these pieces fit together.

What Is Ethereum Gas?

For example, sending ETH from one wallet to another uses less gas than interacting with a complex smart contract.

This system ensures that every operation has a cost, which helps prevent spam and keeps the network efficient.

On Ethereum, gas fees follow a model introduced by EIP-1559, which splits the cost into two parts:

• Base fee - a mandatory fee that is burned (removed from circulation)
• Priority fee (tip) - an extra amount paid to validators to process your transaction faster

According to the Ethereum Foundation, this mechanism improves fee transparency while still allowing users to prioritize speed when needed.

Gas is also widely used across EVM-compatible networks, becoming a standard way to price transactions. However, fees are always paid in each network’s native token. For instance:

• Ethereum → ETH
• BNB Smart Chain → BNB
• Polygon → POL (formerly MATIC)

While many networks follow Ethereum’s fee model, some change how fees are handled. They may burn both the base fee and the tip, or distribute fees differently to validators.

How Ethereum Gas Works (Step-By-Step)

1. You submit a transaction

When you send ETH or interact with a smart contract, you’re asking the network to perform a specific action. Every action requires computational work, and gas measures how much of the network’s resources that action consumes.

2. You set how much gas you're willing to use

Each transaction includes a gas limit, which is the maximum amount of gas you allow for that action. For example, a basic ETH transfer typically requires around 21,000 gas units, while more complex smart contract interactions need significantly more.

If the gas limit is set too low, the transaction can fail before completion - but the gas used up to that point is still consumed. This is why estimating gas correctly matters.

3. The network calculates the fee based on demand

While the amount of gas needed for an action is mostly fixed, the price per unit of gas changes depending on how busy the network is. When demand is high, users compete by offering higher fees to get their transactions processed faster.

4. Your fee is split into base fee and tip (EIP-1559)

Under the EIP-1559 model:

• The base fee is required and gets burned (removed from circulation)
• The priority fee (tip) goes to validators as an incentive to include your transaction quickly

This structure makes fees more transparent while still allowing users to influence speed.

5. Validators process and confirm your transaction

Validators pick transactions based on the fees offered. Higher tips usually mean faster processing, especially when the network is congested. Once your transaction is confirmed, the gas fee is deducted and the action is completed.

How Ethereum Gas Fees Are Calculated: EIP-1559 Explained

Ethereum gas fees are calculated based on three main components: the gas used, the base fee, and a priority fee (tip).

In simple terms, you pay for how much computational work your transaction requires, multiplied by the current gas price set by network demand.

This pricing model, introduced in EIP-1559, was designed to make transaction fees more predictable while still allowing users to pay extra for faster processing.

Example:

• Gas used: 21,000 (standard ETH transfer)
• Base fee: 30 gwei
• Priority fee: 2 gwei

→ Total fee = 21,000 × (30 + 2) = 672,000 gwei

→ = 0.000672 ETH

Base fee

The base fee is the minimum cost required for a transaction to be included in a block. It is automatically set by the network and changes based on how busy Ethereum is.

Here’s how it works:

✔ Each block has a target gas usage (about 50% of the block gas limit)

✔ If the previous block exceeds this target, the base fee increases

✔ If the network is less busy, the base fee decreases

The adjustment is gradual, by up to 12.5% per block, which helps prevent sudden spikes in fees. Importantly, the base fee is burned, meaning it is permanently removed from circulation rather than given to validators.

Priority fee

The priority fee, often called a tip, is an extra amount you can add to incentivize validators to process your transaction faster.

✔ Higher tips → faster inclusion in a block

✔ Lower tips → slower processing, especially during congestion

After Ethereum transitioned to Proof of Stake in 2022, this fee is now paid to validators (not miners). This creates a market where users can compete for priority when the network is busy.

Gas limit

The gas limit is the maximum amount of gas you’re willing to spend on a transaction. It depends on the complexity of the action:

✔ Simple ETH transfer → ~21,000 gas

✔ ERC-20 token approval → ~50,000–65,000 gas, depending on opcode execution and storage access

If your gas limit is too low, the transaction may run out of gas and fail, but you’ll still pay for the computation that was already performed. This is why wallets often estimate gas limits automatically.

How EIP-1559 Impacts ETH Supply

EIP-1559 impacts ETH supply by introducing a fee-burning mechanism that permanently removes a portion of ETH from circulation. As a result, Ethereum’s supply can decrease when network activity is high.

The problem with the old gas auction model

Before EIP-1559, Ethereum used a first-price auction system where users competed by bidding higher gas prices to get their transactions included. While simple in design, this model broke down under real-world conditions.

• The core issue was inefficiency. Users had no reliable reference point for what a “fair” fee should be, so they often overpaid just to avoid delays.
• At the same time, all fees were paid to miners, meaning Ethereum’s supply only moved in one direction: upward.

→ This auction-based system led to unpredictable fees and a poor user experience, especially during network congestion.

What EIP-1559 changed

EIP-1559 replaced the old-fashioned auction model with a hybrid system that separates pricing into two layers: a base fee determined by the network and a priority fee set by users.

The key innovation lies in how the base fee behaves.

• Instead of being paid to validators, it is burned, permanently removing ETH from circulation. This introduces a counterbalance to ETH issuance.
• At the same time, the protocol adjusts the base fee automatically depending on block usage. If blocks are consistently more than 50% full, the base fee increases; if demand drops, it decreases.

Impacts on ETH Supply

Instead of supply only increasing through issuance, ETH is now both created and destroyed. Every transaction contributes to reducing supply through the burned base fee, while new ETH continues to be issued as validator rewards.

After Ethereum transitioned to Proof of Stake, issuance dropped by around 90% - from roughly 13,000 ETH per day to about 1,700 ETH. This reduced the annual issuance rate to around 0.5%-1%, significantly lower than the ~4%-5% seen under Proof of Work.

Meanwhile, during periods of high activity, ETH burning has at times exceeded issuance, effectively turning ETH into a deflationary asset.

Data from Ultrasound Money shows that millions of ETH have been burned since EIP-1559 went live, with peak burn rates occurring during high-demand events like NFT mints.

Why Are Ethereum Gas Fees Still High?

1. Ethereum gas fees are still high because demand for block space consistently exceeds what the network can handle.

Even after EIP-1559 made fees more predictable, it didn’t make them cheaper - it simply made the pricing mechanism more transparent.

2. Another key factor is the nature of what people are doing on Ethereum.

Unlike simple payment networks, Ethereum supports complex smart contracts. Swapping tokens, providing liquidity, or minting NFTs requires significantly more computation than a basic transfer, which increases gas consumption and amplifies total fees.

This leads to an important insight:

How To Avoid Overpaying Ethereum Gas Fees

You can’t completely avoid gas fees on Ethereum, but you can reduce them significantly by being strategic about when and how you transact.

• One of the most effective ways is to use Layer 2 networks like Arbitrum, Optimism, or zkSync.

These networks process transactions off-chain and then settle them on Ethereum, which can reduce fees by 10x-100x depending on network conditions.

• Timing also matters more than most people expect.

Gas fees fluctuate throughout the day, often dropping during off-peak hours like weekends or late-night UTC. Tools like Etherscan or MetaMask’s built-in gas estimator can help you monitor real-time prices and avoid sending transactions when the network is congested.

• Another overlooked strategy is adjusting your gas settings.

Many wallets allow you to manually set your priority fee. If your transaction isn’t urgent, lowering the tip can reduce costs, though it may take longer to confirm. This works especially well when the network is not under heavy load.

• If you frequently interact with dApps, batching multiple actions into a single transaction can also help reduce total gas usage.

Instead of paying separate fees for each step, you combine them into one, saving on overall costs.

Conclusion

Understanding how Ethereum gas works is ultimately about understanding how the network manages scarcity. Gas is the mechanism that decides who gets access to Ethereum’s limited block space and at what cost.

This also explains why gas doesn’t simply “go down” over time. As long as Ethereum remains valuable and widely used, demand will continue to compete for that limited space.