What is notional value
The value of a position at its price: quantity times price. Leverage does not change the notional value, only the margin the position ties up.
In the product
ZML Trade calls it notional value. In the combo table, the Position cell shows Avg price / Quantity / Notional value; that notional value is the combo position quantity times its average cost. An account’s position table has a Notional value column. In the combo parameters, Target position and the minimum and maximum under Per order are all set as amounts (USD), not coin quantities. Z Market Lab shows open interest as notional value in USD.
How to read it
The funding fee is paid on notional value: each payment is the notional value times the funding rate for that period. When ZML Trade books a combo’s funding, it takes the notional value as the combo position quantity times the average cost, not the market price at settlement, so it can differ slightly from what the exchange actually charged or paid. On cross margin the position ties up about notional value ÷ leverage. Example: at 10×, a 1,000 USD position ties up about 100 USD of margin.