A trade can cost several things. On the web, the review screen shows each one before you confirm. In the Telegram bot a buy runs when you tap the amount, so check the token card first.
| Cost | What it is | Where you see it |
|---|---|---|
| Network fee (gas) | Charged by the chain, in its own coin, even when a trade fails on most chains. On NEAR the unused part of the attached gas is refunded. | The wallet keeps a reserve for it. On the web, Max leaves enough. |
| Pool fee | Charged by the trading pool. It is already in the quote. | Pool fee row in the web review |
| Token tax | A share some tokens take on every buy or sell, set by the token's own contract. | Buy and sell tax rows in the web review, and the token card |
| Price impact | How much your own size moves the price in a small pool. | Price impact row in the web review, amber above 2% and red above 5%. The bot shows it as a number on the full token card. |
| Slippage | The room you allow for the price to move before a trade cancels. | Slippage row, and Minimum received |
| Bridge cost | What a move between chains costs. It is built into the amount you receive. | The quote on the Bridge screen |
Minimum received
This is the number that protects you. The pool must pay at least this much or the swap is refused on chain. A refused swap does not buy anything, though the network fee for the attempt can still be spent.
Gas reserve
On NEAR, a trade attaches far more gas than it uses, and the chain refunds the unused part a moment later. That is why Rex keeps about 0.25 NEAR free: the up front amount is larger than the final cost. Most of it comes back.