Bid-Ask Spread
The gap between the highest price buyers will pay (bid) and the lowest sellers will accept (ask). Crossing the spread is the immediate cost of a market order. Liquid ETFs trade with penny spreads; thin instruments can cost many times more — a real hurdle for strategies that trade frequently.
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Related terms
SlippageThe difference between the price a strategy expected and the price it …LiquidityHow much of an asset can be traded quickly without moving its price. D…
Backtests are hypothetical, computed by DeployQuant's engine on minute-resolution consolidated US market data (2021-01-04 to 2026-07-17, $10,000 starting capital, no margin, fees and slippage not modeled) and do not guarantee future results. Nothing on this page is investment advice. Live trading involves risk of loss.