Wei to Ether Converter

Type a value in wei, gwei, or ether and the converter shows the equivalent in the other two denominations. Ethereum's smallest unit is wei (10^18 of these to 1 ETH); gwei (10^9 wei) is the working unit for gas prices; ether is the human-facing unit.

Gas prices on Ethereum mainnet typically sit between 5 and 100 gwei depending on demand. A standard ERC-20 transfer uses ~65,000 gas units; a Uniswap swap uses 150,000-250,000. Multiply gwei × gas units × 10^-9 to get the ETH cost of a transaction.

The converter handles the decimal-place gymnastics so you don't have to count zeros. Paste raw wei output from a JSON-RPC call (eth_getBalance returns wei) and read off the ETH balance directly.

The denominations exist because Ethereum at the EVM level uses integer arithmetic only — no floats. Smart contracts manipulate balances in wei to avoid floating-point rounding bugs that would compound across millions of transactions. 1 ETH = 10^18 wei means a uint256 can represent ~1.16 × 10^59 ETH worth of value, which is comfortably larger than the actual ETH supply will ever be. Gwei sits in the middle as the human-readable gas-price unit because gas prices in raw wei look like 40,000,000,000 — too many zeros to skim safely.

Worked example: a wallet's eth_getBalance RPC call returns 1500000000000000000. Run the converter: 1.5 ETH. Or read the gas-price oracle showing 35 gwei: that's 0.000000035 ETH per gas unit. Multiply by a 65,000-gas ERC-20 transfer: 65000 × 35 × 10^-9 = 0.002275 ETH. At an ETH price of $2,000, the transaction costs about $4.55 in gas. The converter spits out the unit conversions; multiplying by gas units and ETH price gives you the dollar cost.

Gotchas: hex-encoded RPC responses. eth_getBalance returns 0x14d1120d7b160000, which is hex for 1.5 × 10^18. Convert hex to decimal first, then plug into the converter. Most modern web3 libraries (ethers.js, viem) wrap this, but raw curl calls hit you with the hex. Also: not every chain uses 18 decimals. USDC has 6 decimals; some BEP-20 tokens have 8 or 9. The wei/gwei/ether scheme is Ethereum-native but the principle (smallest unit × 10^decimals = display unit) applies broadly.

Real-world workflow: pulling balances from a wallet via JSON-RPC. eth_getBalance returns a hex-encoded wei value like 0x1234abcd. Convert hex → decimal → divide by 10^18 → display ETH. Most web3 libraries (ethers.js's formatEther, viem's formatEther) do this in one call. The converter exists for the 5% of cases where you're in a debugger or reading raw RPC output and want a quick sanity check without spinning up a script.