The multiple of your account size you're allowed to trade — 1:100 leverage means $1,000 controls $100,000 notional.
Leverage amplifies both gains and losses. A 1% price move on a fully leveraged 1:100 position is a 100% P&L move on the underlying margin. Regulated retail leverage caps: 1:30 (ESMA/FCA majors), 1:50 (NFA US majors), up to 1:500–1:1000 (offshore).
Also called:
margin ratio
Example
1:100 leverage. To trade 1 standard lot of EUR/USD (€100,000) you need $1,000 margin (and the equivalent value in EUR).
Watch out
Beginners blow up by using max leverage as license to oversize. The right size depends on stop distance and risk per trade, not on the broker's leverage cap.
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