Definition
Order size describes how much an order requests. Depending on the market and interface, it may be entered as base-asset quantity, quote-currency value, or number of contracts. It is distinct from the amount eventually executed and from the account’s total position after multiple trades.
How It Works
For a spot order of 0.2 BTC at a hypothetical limit of 50,000 USDT per BTC, the order’s notional value is 10,000 USDT before fees. Contract orders instead require the instrument’s multiplier or face-value rules. Minimum quantities, permitted increments, and maximum order sizes determine whether the request is valid.
Key Considerations
A large order relative to available depth can create slippage or only fill partly. Available balance, margin requirements, and reserved funds can further constrain size. For leveraged products, the margin posted is not the same as exposure. Confirm the unit shown in the order field before submitting; a number expressed in contracts cannot automatically be read as coins.