Enter a gas price in gwei to see it in ETH and wei, then multiply by a gas limit to get the real fee of a transfer, token transfer or swap. Everything is computed locally with exact integers.
A gwei to ETH converter divides a gas price or fee quoted in gwei by 109 to express it in ETH, and multiplies by 109 to get wei. Combined with a gas limit it becomes a gas fee calculator: fee in ETH = gas units × gas price in gwei ÷ 109, so 21,000 gas at 20 gwei is 0.00042 ETH.
Beginners often read a gas tracker showing "25 gwei" and assume that is the cost of a transaction. It is the price per unit of gas. A simple transfer needs 21,000 units, so the fee is 21,000 × 25 gwei = 525,000 gwei = 0.000525 ETH. Contract interactions use more gas and therefore cost proportionally more at the same price.
Since the London upgrade every block has a base fee that rises when blocks are full and falls when they are not. You add a priority fee (tip) for the validator and set a max fee you are willing to pay. The effective gas price is base fee + tip, never more than your max; the difference is refunded. The base fee is burned, the tip goes to the validator.
| Gas price | 21,000 gas (transfer) | 65,000 gas (ERC-20) | 150,000 gas (swap) |
|---|---|---|---|
| 5 gwei | 0.000105 ETH | 0.000325 ETH | 0.00075 ETH |
| 20 gwei | 0.00042 ETH | 0.0013 ETH | 0.003 ETH |
| 50 gwei | 0.00105 ETH | 0.00325 ETH | 0.0075 ETH |
| 100 gwei | 0.0021 ETH | 0.0065 ETH | 0.015 ETH |
For the full unit table including kwei, szabo and finney see the Ethereum unit converter.
1 gwei = 0.000000001 ETH (10-9). 100 gwei = 0.0000001 ETH. Gwei is a unit of price per gas, so the fee you pay is gas price × gas used.
Fee = gas used × gas price. A plain ETH transfer uses exactly 21,000 gas. At 20 gwei that is 420,000 gwei = 0.00042 ETH. With EIP-1559 the gas price you effectively pay is base fee + priority tip, capped by your max fee.
ETH transfer 21,000; ERC-20 transfer roughly 45,000 to 65,000; Uniswap swap roughly 100,000 to 200,000; NFT mint 80,000 to 300,000. The calculator has preset buttons; your wallet shows the exact estimate before you sign.
You type the ETH price yourself. The page makes no network requests, so there is no live price feed and no tracking. Fill in today's price from your exchange for a quick estimate.
The arithmetic is the same (gas × price in gwei), but the native token differs: MATIC/POL, ETH on Arbitrum and Base, BNB on BNB Smart Chain. Treat the ETH result as the native coin of that chain.