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Margin Calculator

Before you place a leveraged trade, work out exactly how much margin it will tie up. The calculator takes your instrument, lot size, entry price and leverage, and returns the required margin in your account currency — so you know whether the trade fits inside your free balance and how much room you have for other positions.

How to use it

  1. Account currency. Select the currency your account is denominated in. The required margin is returned in this currency.
  2. Account balance (optional). Enter your balance if you want to see what percentage of your account the margin represents. Leave blank if you only need the cash margin figure.
  3. Instrument. Search and select the pair, index or CFD. The calculator pulls the correct contract size and base currency for the conversion.
  4. Lot size. Enter the position size — 1.0 is one standard lot, 0.1 is a mini, 0.01 is a micro.
  5. Entry price. The price at which you plan to enter. Margin scales with notional value, so the entry price matters.
  6. Leverage (1:X). Enter the leverage offered by your broker for this instrument. Typical retail forex leverage runs from 1:20 to 1:30 under ESMA/FCA rules, up to 1:500 with some offshore brokers.
  7. Hit Calculate margin. The calculator returns the required margin in your account currency, alongside the notional position value.

A worked example

Suppose you have a 5,000 EUR account and want to take a 1-lot long on EUR/USD at 1.0850 with 1:30 leverage.

  • Account currency: EUR
  • Account balance: 5,000 EUR
  • Instrument: EUR/USD
  • Lot size: 1.0 → 100,000 EUR notional
  • Entry price: 1.0850
  • Leverage: 1:30

The notional value is 100,000 EUR. At 1:30 leverage, the required margin is 100,000 ÷ 30 = 3,333 EUR — about 67% of the account balance. That’s a useful warning sign: a single trade this size doesn’t leave much free margin for other positions or for drawdown before triggering a margin call.

When to use it

  • Pre-trade affordability check. Before placing a larger-than-usual trade, confirm you have enough free margin to open it. Useful for indices and crypto CFDs where margin requirements can be much higher than on forex.
  • Multi-position planning. If you tend to hold several open positions at once, total margin usage adds up quickly. Run the calculator for each planned trade and check the cumulative margin against your free balance.
  • Comparing leverage scenarios. See how the same trade behaves at 1:30 vs 1:100 vs 1:500. It’s a quick visual on why retail leverage caps exist — higher leverage means lower margin used, but also less buffer against adverse moves.
  • Margin-call awareness. If a trade uses 50%+ of your account as margin, even modest adverse moves can push the account into a margin-call zone. The calculator surfaces that risk before you click.
  • Sizing within a strategy. Some strategies pyramid into a position or scale across correlated instruments. Use the calculator to keep total exposure (and total margin) inside sensible limits.

The formula

Show the maths

The calculator uses this relationship:

Notional value = Contract size × Lot size × Entry price

Required margin (base currency) = Notional value ÷ Leverage

Then converts into your account currency:

Required margin (account currency) = Required margin (base currency) × Base-to-account FX rate

Where:

  • Contract size is usually 100,000 units per standard lot for forex; indices, commodities and CFDs vary by instrument.
  • Leverage is whatever your broker offers for the instrument — this can differ between forex majors, minors, exotics, indices and shares.
  • Base currency is the first currency in a forex pair, or the instrument’s denominating currency for indices and CFDs.

Common mistakes

  • Confusing leverage and margin. 1:30 leverage means 3.33% margin. 1:100 leverage means 1% margin. The two move inversely.
  • Using the wrong leverage tier. Brokers often apply different leverage to different instrument classes — e.g. 1:30 on forex majors, 1:20 on minors, 1:10 on indices, 1:2 on crypto. Use the tier that applies to your specific instrument.
  • Forgetting overnight margin requirements. Some brokers raise margin requirements over weekends or around major news. The calculator shows the standard requirement; check your broker’s terms for adjustments.
  • Treating used margin as risk. Margin is what’s locked up; risk is what you’d actually lose if the stop hits. They’re not the same number — size your trade with the lot size or position size calculator, and use this one only to confirm the trade fits inside your free balance.

These calculators are for educational purposes only. Trading leveraged products carries a high level of risk and may not be suitable for all investors.