Trade WETH

WETH is ether repackaged as an ERC-20 token standard — symbol WETH, 18 decimals, same value as ETH. Native ETH predates the ERC-20 standard, so it doesn't behave like other tokens inside smart contracts. WETH9 fixes that: deposit ETH, get an ERC-20 that any DeFi protocol can hold, transfer, and account for uniformly.

The peg is mechanical, not market-driven. Depositing ETH into the WETH9 contract mints the same amount of WETH; withdrawing burns WETH and returns the same amount of ETH. One WETH is a claim on one ETH held by the contract — there is no issuer discretion and no separate price formation at the wrapping layer.

You get WETH two ways: deposit ETH directly into the wrapping contract (one-for-one before network fees), or acquire it on a DEX like any other token. Depositing is the clean route when you already hold ETH and just need the ERC-20 form.

Getting out is the reverse: a withdraw call burns your WETH and returns the same amount of ETH to your wallet. Wrapping and unwrapping are not swaps: there's no pool, no price impact, and no counterparty rate; it's a fixed smart-contract conversion, and the only cost is gas.

Trading WETH means exchanging it for another token at a rate set by available on-chain liquidity — not by the wrapping contract. In an automated market maker, pools and routers use available reserves to quote the route; you pick WETH and an output token, and your wallet signs the final transaction. The execution contract moves your approved WETH through the pools and returns the output token straight to your wallet.

Three costs stack up: network gas (paid in native ETH), the pool fee baked into the route, and price impact from trade size relative to pool depth. The route reports the minimum received and deadline; the quoted price and the executed price can drift if the market moves. If you're selling WETH for the first time from a wallet, expect an approval step first: an ERC-20 allowance (or a supported permit) granting the specific spender contract permission to transfer it. Approval is a separate transaction from the swap itself — a single-hop swap needs the allowance in place before it can execute.

ETH and WETH have the same value at the wrapping layer but different plumbing. ETH is the native asset — you need it for gas on Ethereum, and it's what lives in your wallet when you're not touching DeFi. WETH is the ERC-20 wrapper — it's what most DEX pools, lending markets, and NFT contracts actually quote against, because it plugs into the standard token interface.

Hold ETH for gas and general use; hold WETH when you're actively trading or deploying into protocols that take ERC-20. An all-WETH wallet can't pay to unwrap itself because transaction fees are charged in native ETH.

Every step costs gas, paid in native ETH: the wrap, the unwrap, each approval, and each swap; the Ethereum gas fee guide explains the fee mechanism. Gas varies with network congestion and the fee you set, and completion depends on on-chain inclusion and confirmation — timing isn't fixed.

A DEX swap layers two more costs on top of gas: the pool fee the route passes through, and price impact from how your order moves the pool. The quoted minimum received is your floor — if the route can't beat it before your deadline, the transaction reverts and you've still spent gas. This price difference between the quote and execution is slippage in crypto; size your trade against the impact figure, not just the headline quote.

Trade WETH is safe to use only when the contract, interface, router, and chain match the transaction you intend to make. The canonical WETH9 contract on Ethereum mainnet is 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2 on chain ID 1. WETH variants on other networks are different contracts entirely and must be verified separately.

Non-custodial execution keeps keys in your wallet, but smart-contract, frontend, wallet, RPC, approval, routing, and liquidity risks all remain. Before you sign, confirm the URL, the network, the token address, the spender on any approval, and what the wallet prompt is actually asking for.

Wrong network. WETH exists on many chains under the same ticker with different contracts. Match the chain ID and address to the network you intend — a mainnet address means nothing on an L2.

Can't pay gas. Gas is paid in native ETH, not WETH. If your wallet is all WETH, you can't even afford the unwrap.

Swap won't execute. Usually the spender contract has a missing or insufficient ERC-20 allowance, or the route's price slipped past your minimum received before the deadline. Re-check the approval, re-quote, and resubmit.

Wrong action. Wrapping ETH and swapping WETH are different operations. To convert ETH to WETH one-for-one, use the deposit function instead of routing through a liquidity pool.