Market Order

A market order executes immediately at the best available price, prioritizing speed of execution over price certainty. You get the trade done now, accepting whatever the market offers. Market orders guarantee execution (assuming any liquidity exists) but provide no price guarantee, the actual execution price depends on current order book depth or AMM pricing.

In liquid markets with tight spreads, market orders execute close to displayed prices. In illiquid markets, market orders suffer slippage: the execution price worsens as the order consumes available liquidity across multiple price levels. A large buy market order might purchase at $100, $101, $102, and beyond as it eats through the ask side of the order book.

This price impact can be substantial for large orders relative to market depth. Professional traders typically avoid market orders for size, using limit orders or algorithmic execution to minimize impact. On DEXs, all swaps are effectively market orders against AMM pools, with slippage tolerance parameters protecting against excessive price impact.

MEV (Maximum Extractable Value) makes on-chain market orders particularly risky: bots can see pending transactions and sandwich them, buying before and selling after to extract value. Private mempools and MEV-protection services help mitigate this risk.