Contract Multiplier
The dollar amount assigned to each index point (or unit) of a futures contract, converting price moves into P&L.
P&L per contract = Multiplier × Point Change
The contract multiplier is the dollar value assigned to one point of movement in the futures price. For index futures it converts an abstract index level into real dollars. It is sometimes called the point value or dollar value per point.
Multiplier × price change = dollar P&L per contract. Knowing the multiplier is step one of any position-sizing calculation.
On the desk
ES multiplier = $50. NQ multiplier = $20. A 10-point ES rally = $500/contract. The same 10-point NQ rally = $200/contract. YM multiplier = $5, so 100 Dow points = $500/contract.