Ethereum Gas Fee Oracle

What is the Ethereum base fee?

The base fee is the minimum fee per unit of gas required to include a transaction in the current Ethereum block, introduced by EIP-1559. It adjusts algorithmically each block based on network demand: when blocks are more than 50% full, the base fee rises; when less than 50% full, it falls. The base fee is burned (destroyed), not paid to validators.

What is gwei?

Gwei (gigawei) is the denomination used to express Ethereum gas prices. 1 gwei = 0.000000001 ETH (one billionth of an Ether). A typical ETH transfer at 15 gwei base fee costs 21,000 × 15 gwei = 315,000 gwei = 0.000315 ETH.

What is the difference between base fee and priority fee?

Under EIP-1559, the total gas price has two components: (1) the base fee — algorithmically set and burned; and (2) the priority fee (tip) — paid directly to the validator who includes your transaction. A higher priority fee increases the incentive for validators to include your transaction sooner.

When is the cheapest time to transact on Ethereum?

Gas fees are lowest when network demand is low — typically between 00:00 and 07:00 UTC (overnight in US/Europe time zones) and on weekends. Fees spike during peak DeFi activity, major token launches, NFT mints, or high-volatility market events. The "Low Load" congestion label on this tool indicates the most cost-efficient windows.

Why does a Uniswap swap cost more gas than an ETH transfer?

Ethereum gas is proportional to computational complexity. A simple ETH transfer requires 21,000 gas (the minimum). A token (ERC-20) transfer requires ~65,000 gas for the extra token-contract logic. A Uniswap swap executes a smart contract routing algorithm, pool math, and token approvals — typically 150,000–250,000 gas. This tool uses 200,000 gas as the Uniswap estimate.