A DEX does not float in space — it runs on a specific blockchain, and that choice quietly decides your fees, your speed and which tokens you can even reach.
The networks you will meet
| Network | What it is | Fees | Notes |
|---|---|---|---|
| Ethereum | The original smart-contract chain (L1) | High at peak | Deepest liquidity, most tokens |
| Arbitrum · Base · Optimism | Layer-2s built on Ethereum | Low | Inherit much of Ethereum's security |
| BNB Chain | Independent EVM chain | Low | Home of PancakeSwap |
| Solana | Fast, non-EVM L1 | Very low | Home of Jupiter and Raydium |
| Sui · Aptos · Cosmos… | Newer ecosystems | Varies | Their own wallets and tokens |
EVM vs. non-EVM
Most chains are EVM-compatible (Ethereum, its layer-2s, BNB Chain), meaning the same wallet — such as MetaMask — and similar tokens work across all of them. Solana is the big non-EVM exception, with its own wallets (Phantom) and token standard. That is why you cannot simply point MetaMask at Solana.
Why the network decides your costs
- Fees — the very same swap can cost a few dollars on Ethereum and a fraction of a cent on Solana or a layer-2.
- Tokens — a token lives on a specific chain; if it is on Base, your wallet must be on Base to trade it.
- Liquidity — a coin can exist on several chains, with different pool depths on each.
The rule that prevents most mistakes
Your wallet, the DEX and the token all have to be on the same network. Switching networks is a one-click action in your wallet — but sending tokens to the wrong one is a common and costly error. Moving assets between chains needs a bridge, which we cover in Module 4. For beginners, a cheap layer-2 like Base or Arbitrum, or Solana, is the friendliest place to start: low fees mean small mistakes stay small.
- Having your wallet on the wrong network and thinking your tokens have vanished.
- Sending tokens to an exchange or address on a different chain — they can be lost for good.
- Assuming a token on one chain is the same as the identically-named one on another.