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Forex Margin Calculator

A margin calculator that shows how much of your deposit a leveraged position ties up, and why the leverage number is a limit, not a target.

Compiled by the IonyxHub library desk. Updated 26 September 2026. How lessons are checked

Margin calculator

Required margin
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Glass euro symbol and a glass dollar symbol balanced on a sleek scale

This margin calculator works out the deposit, called required margin, that a broker sets aside when you open a leveraged position. Pick the pair, enter the price, position size and the leverage available to you, and the tool shows the position's full value alongside the margin it needs.

The formula

Position value = lots × 100,000 × value of one unit of the base currency in USD
Required margin = position value ÷ leverage

When the base currency is the US dollar, as in USD/JPY, one unit is simply $1. When the dollar is the quote currency, as in EUR/USD, one unit is worth the current price in dollars.

Worked examples

The numbers are illustrative.

  • EUR/USD at 1.1000, 0.5 lots: position value = 0.5 × 100,000 × 1.1000 = $55,000. At 30:1, margin = $55,000 ÷ 30 = about $1,833.33. At 50:1 it would be $1,100.
  • USD/JPY, 1 lot: position value = $100,000. At 30:1, margin = about $3,333.33.

How to read the result: margin level

Brokers track your margin level: account equity divided by the margin in use, as a percentage. Suppose you hold the 0.5-lot EUR/USD trade above with $2,500 of equity. The margin level is $2,500 ÷ $1,833.33 = about 136%.

In the UK and EU, a broker must begin closing a retail client's positions once the margin level falls to 50%. Here that would happen at equity of about $916.67, which means a loss of about $1,583.33. With 0.5 lots of EUR/USD worth $5 per pip, that is roughly 317 pips against you. The margin you post is therefore not the most you can lose on paper; it is what the broker holds while losses run against the rest of your account.

Retail caps in the UK and EU are 30:1 on major currency pairs and 20:1 on gold and other pairs. Using less leverage than allowed leaves more room before a close-out. The position size calculator helps choose a size from risk rather than from available leverage.

Leverage magnifies losses as much as gains. Most retail accounts trading leveraged CFDs lose money. Negative balance protection applies to retail clients in the UK and EU but may not apply elsewhere.

Quick answers

Is required margin a fee?

No. It is part of your own money set aside while the position is open, and it is released when you close. Losses, fees and financing are separate.

What is a margin call?

A warning that your equity is close to the level at which the broker may close positions. Rules on when positions are closed vary by country and broker.

Sources

  • UK Financial Conduct Authority, CFD rules for retail clients
  • European Securities and Markets Authority, CFD product intervention measures

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