Error message: Transaction is expected to fail#

This error can appear while swapping on CenturionDEX. It is meant to prevent you from paying the network cost for a swap that would fail.

A few reasons it may appear:

  1. A variable token buy or sell fee. The swap's slippage must be higher than the token's fee; if the fee rises, increase your slippage. See How to find a token's fee. For example, if the token has a 10% sell fee, try a slippage of 11–14%.
  2. An unsellable token. Malicious creators can add code preventing anyone but themselves from swapping. See Unsellable-token scams.
  3. A non-standard approval function. Try revoking existing approvals for the token, then swap again.
  4. A token causing a mathematical error. Rebase and fee-on-transfer tokens have internal math that changes a swap's output. Try swapping an even or exact input or output amount.