Slippage calculator
The price you see when placing an order and the price it actually fills at often differ by a little, and that is slippage. Above, enter the expected price and the actual fill price to work out the slippage percent and how much extra you paid (or received less); you can also use a 'slippage tolerance' to derive a worst acceptable fill price. Everything runs in your browser. Nothing is uploaded or stored.
*20% spot fee discount; the actual rate shown on Binance's page applies and may change with policy.
How slippage is calculated
Slippage measures how far the fill price deviates from the expected price: (fill price − expected price) ÷ expected price × 100%. A higher fill on a buy and a lower fill on a sell are both the adverse direction for you. Multiply by quantity and you know what that deviation is in money: expected 100, filled 100.5, 10 units bought, means 5 extra paid.
Conversely, if you have a tolerance limit in mind (say 0.5%), you can derive the worst acceptable fill price: for a buy, expected price × (1 + tolerance); for a sell, expected price × (1 − tolerance). When placing an order on a DEX, this is the slippage protection value you should set: too loose and you can get sandwiched, too tight and the order may fail to fill.
Spot matching on Binance generally has very small slippage; what really exposes you to slippage is moving bStocks on-chain and swapping in decentralized venues like PancakeSwap LP. The thinner the liquidity and the larger the single trade, the worse the slippage, so be sure to set a slippage cap in the trading interface.
There are other costs beyond slippage
The real cost of a trade = the spread (slippage) + fees + (if on-chain) gas. Estimate fees with the Binance spot fee calculator; the on-chain gas for a withdrawal is small but don't forget it, see withdrawing to the Web3 Wallet, FAQ. To work out exactly how much this trade made or lost, use the P&L calculator.