Slippage
The difference between the price you expect for a trade and the price you actually get.
Slippage is the gap between the expected and the executed price of a trade. It happens because prices move between quote and execution, and because large orders can use up the best available liquidity and fill at worse prices.
On decentralized exchanges, slippage is visible as a setting: you choose how much worse than the quote you are willing to accept before the trade is cancelled. Setting it too high can expose you to price manipulation; setting it too low can make trades fail.
On instant swap services, slippage appears as the difference between a floating-rate estimate and the final amount. Fixed-rate quotes remove it for the user, because the provider absorbs price movement during the quote window. Slippage tends to be larger for low-liquidity coins, big amounts and fast-moving markets, so splitting a large swap or choosing a fixed rate can help.
