Forex Margin Calculator — Required Margin & Free Margin
Calculate the exact margin required to open a forex position. Enter your account balance, leverage, lot size, and current pair price to instantly see required margin, free margin, margin level, and your margin call risk status.
Your total account size
The pair price prefills; edit it to match your broker
Position size unit
Leverage: 1:100
Number of lots to trade
Loading live rates…
Required Margin
$1,086.96
Free Margin
$3,913.04
Notional Value
$108,696.00
Position Units
100,000
Max Lots
4
Margin Level
460.00%
Safe
Safe zone (above 200%) — free margin to absorb a move against you
Last reviewed · How we check our calculators
How to Use the Forex Margin Calculator
Using the Forex Margin Calculator takes under a minute. Enter five values: your account balance in dollars, the leverage ratio your broker provides (e.g. 1:100), the lot size you plan to trade, the current pair price (e.g. EUR/USD at 1.0850), and select whether you are trading standard, mini, or micro lots. Your results update instantly as you type.
The primary output is the required margin — the amount your broker will lock as collateral for the trade. You will also see your free margin (available funds after the trade opens) and your margin level percentage, marked on one scale: Safe above 200%, a warning colour from 100% to 200%, and red below 100% (margin call risk).
The Max Lots figure shows the largest position your account can support at current leverage without exceeding your balance. Use this to understand the limits of your account before placing a trade.
The Formula
The margin calculator uses four core formulas:
- Notional Value: Notional = Lots × Lot Units × Pair Price
Example: 1 standard lot × 100,000 units × 1.0850 (EUR/USD) = $108,500 - Required Margin: Margin = Notional Value ÷ Leverage
Example: $108,500 ÷ 100 = $1,085 - Free Margin: Free Margin = Account Balance − Required Margin
Example: $5,000 − $1,085 = $3,915 - Margin Level: Margin Level (%) = (Account Balance ÷ Required Margin) × 100
Example: ($5,000 ÷ $1,085) × 100 = 461%
Brokers typically issue a margin call when margin level falls below 100% and may automatically close positions (stop-out) at levels between 20–50%, depending on the broker. Always maintain a margin level well above 200% to absorb adverse price movements.
Practical Examples
Example 1 — EUR/USD Standard Lot with 1:100 Leverage
A trader has a $5,000 account, uses 1:100 leverage, and wants to buy 1 standard lot of EUR/USD at 1.0850.
- Lot units: 1 × 100,000 = 100,000
- Notional value: 100,000 × 1.0850 = $108,500
- Required margin: $108,500 ÷ 100 = $1,085
- Free margin: $5,000 − $1,085 = $3,915
- Margin level: ($5,000 ÷ $1,085) × 100 = 461% — Safe
With 461% margin level, this account has substantial buffer. The price of EUR/USD would need to move significantly against the trader before approaching a margin call.
Example 2 — GBP/USD Mini Lot with 1:50 Leverage
A newer trader with a $2,000 account uses 1:50 leverage and trades 2 mini lots of GBP/USD at 1.2700.
- Lot units: 2 × 10,000 = 20,000
- Notional value: 20,000 × 1.2700 = $25,400
- Required margin: $25,400 ÷ 50 = $508
- Free margin: $2,000 − $508 = $1,492
- Margin level: ($2,000 ÷ $508) × 100 = 394% — Safe
Even with lower leverage, the smaller position size relative to account balance keeps the margin level comfortably safe. Always check your free margin before opening additional positions.
Frequently Asked Questions
Forex margin is the collateral your broker requires you to deposit to open and maintain a leveraged position. It is not a fee — it is a good-faith deposit that is held while your trade is open. Margin is calculated as a percentage of the full notional value of the trade. For example, at 1:100 leverage (1% margin requirement), a $100,000 position requires only $1,000 in margin. When you close the trade, your margin is released back to your free balance.
Margin level is the ratio of your account equity to your used margin, expressed as a percentage: (Equity ÷ Used Margin) × 100. It tells you how much buffer you have before a margin call. Most brokers issue a margin call warning at 100% margin level and begin closing positions automatically (stop-out) at 20–50%. Maintaining a margin level above 200% is generally considered safe practice for active forex traders.
Free margin is the dollar amount available in your account after accounting for the margin locked in open positions: Free Margin = Equity − Used Margin. Margin level is a percentage ratio that measures the health of your account relative to your exposure. You need free margin to open new trades; you need margin level above the broker's stop-out threshold to keep existing trades open.
Leverage and required margin are inversely proportional. Higher leverage means lower required margin for the same position size. At 1:100 leverage, a $100,000 position requires $1,000 in margin (1%). At 1:50, the same position requires $2,000 (2%). Higher leverage reduces upfront capital requirements but also means your account equity changes faster relative to your margin — increasing the risk of a margin call if the market moves against you.
A margin call occurs when your margin level drops below your broker's margin call threshold, typically 100%. The broker will alert you to deposit more funds or reduce your position size. If the margin level continues to fall to the stop-out level (often 50% or lower), the broker will automatically close your positions to prevent a negative balance. To avoid margin calls: use appropriate position sizing, keep leverage reasonable, always maintain free margin above 50% of your balance, and use stop-loss orders on every trade.
Sources
- Margin (finance) (Wikipedia)
- Kathy Lien, Day Trading and Swing Trading the Currency Market (3rd ed.) (Wiley, 2015)
Embed This Calculator on Your Website
Free for blogs, forums and tipster sites. Paste this HTML where the calculator should appear — it resizes automatically.
<div class="calcvault-embed" style="max-width:700px;margin:0 auto;">
<script src="https://www.calcvault.co/widget.js" data-calc="forex-margin-calculator" data-backlink="inline"></script>
<p style="text-align:center;margin:6px 0 0;font-size:12px;font-family:system-ui,sans-serif;"><a href="https://www.calcvault.co/calculators/forex-margin-calculator">Forex Margin Calculator by CalcVault</a></p>
</div>