The Leverage Formula (with a Worked Example)
Account leverage = notional value / margin
Maximum position = equity x leverage / (contract size x price)
Effective leverage = total notional / equity
Worked example: one standard lot of EURUSD at 1.0850 is 108,500 of notional. Held on 1,085 of margin, that is 108,500 / 1,085 = 1:100 account leverage. On a 10,000 account, the effective leverage is 108,500 / 10,000, roughly 11x, the number that actually reflects your risk.
Margin and Max Size by Leverage (EUR/USD)
| Leverage | Margin for 1 lot | Max lots on $5,000 |
|---|---|---|
| 1:30 (ESMA retail cap) | $3,616.67 | 1.38 lots |
| 1:100 | $1,085.00 | 4.61 lots |
| 1:200 | $542.50 | 9.22 lots |
| 1:500 | $217.00 | 23.04 lots |
Account Leverage vs Effective Leverage
Account leverage is a ceiling: 1:100 means you are allowed to control up to a hundred times your margin. Effective leverage is what you are actually doing: your open notional divided by your equity. You can hold a 1:500 account and run at 3x effective leverage, or hold a 1:30 account and still run at 25x by opening a large position. The account number is a limit, the effective number is the risk.
This is the honest core of the tool. A trader who fixates on "low leverage keeps me safe" but opens oversized positions is running high effective leverage regardless of the account setting. Watch the effective figure the calculator shows, and keep it modest. That, not the broker leverage tier, is what survives a bad run.
Leverage Caps by Regulator
Regulated brokers cap leverage to protect retail traders from themselves. Under ESMA rules in the European Union, retail forex leverage is limited to 1:30 on major pairs and less on volatile instruments. The United States caps major-pair leverage at 1:50 through the NFA. Offshore brokers commonly offer 1:500 or higher.
Higher leverage lowers the margin each position ties up, which is why offshore accounts feel roomy, but it changes nothing about the risk of any single trade. The presets in this calculator let you see exactly how the margin and the maximum size shift between 1:30 and 1:500 while the position risk stays put.
Does Leverage Change Your Risk?
By itself, no. Leverage changes how much margin a position needs, not how much you lose if price moves against you. Your loss is set by your position size and your stop distance, which is why risk is controlled by position sizing, not by the leverage dial. Two traders with the same position take the same loss whether their accounts are 1:30 or 1:500.
What leverage does change is temptation. Cheap margin makes it easy to open a size your account cannot survive, and to hold several such positions at once. Decide your position size from risk first with the position size calculator, then use leverage only to check that the margin fits, never as a reason to trade bigger.
