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Margin Call Calculator
Calculate the exact stock price that triggers a margin call. See your equity ratio, leverage, interest cost, and a full scenario table for price changes.
Reg T minimum: 50%
FINRA minimum: 25%
Additional cash beyond initial margin
Margin Call Priceโง
$66.67
Stock must drop 33.3% to trigger
Total Positionโง
$20,000.00
200 shares ร $100
Your Equityโง
$10,000.00
Equity ratio: 50.0%
Loan Amountโง
$10,000.00
Borrowed from broker
Leverageโง
2.00ร
Total position / your equity
Interest Costโง
$65.75
8% for 30 days
Margin Safety Buffer
Margin Call (25%)
0%Current: 50.0%100%
Price Scenarios
| Price ฮ | Stock Price | Position | Equity | Equity % | Status |
|---|---|---|---|---|---|
| -40% | $60.00 | $12,000.00 | $2,000.00 | 16.7% | โ ๏ธ Call: $1,000.00 |
| -30% | $70.00 | $14,000.00 | $4,000.00 | 28.6% | โ OK |
| -20% | $80.00 | $16,000.00 | $6,000.00 | 37.5% | โ OK |
| -10% | $90.00 | $18,000.00 | $8,000.00 | 44.4% | โ OK |
| +0% | $100.00 | $20,000.00 | $10,000.00 | 50.0% | โ OK |
| +10% | $110.00 | $22,000.00 | $12,000.00 | 54.5% | โ OK |
| +20% | $120.00 | $24,000.00 | $14,000.00 | 58.3% | โ OK |
| +30% | $130.00 | $26,000.00 | $16,000.00 | 61.5% | โ OK |
| +40% | $140.00 | $28,000.00 | $18,000.00 | 64.3% | โ OK |
Planning notes, formulas, and examples
About the Margin Call Calculator
A margin call occurs when your account equity falls below the broker's maintenance margin requirement โ typically 25% for stocks under FINRA rules. Understanding exactly where your margin call trigger sits is critical for managing leveraged positions.
When you buy stock on margin, you contribute only a fraction (the initial margin, usually 50% under Reg T) and borrow the rest from your broker. As the stock price falls, your equity shrinks while the loan stays fixed. If equity drops below the maintenance margin percentage, the broker demands additional funds โ or liquidates your position.
This calculator computes the exact margin call trigger price, your current equity ratio and leverage multiplier, the interest cost of your margin loan, and a detailed scenario table showing what happens to your account as the stock price moves ยฑ40%. The safety buffer visualization shows exactly how far you are from a margin call at any moment.
When This Page Helps
Leveraged positions amplify both gains and losses. This calculator shows the exact price at which your broker forces action, so you can set stop-losses appropriately and avoid the surprise of a forced liquidation. Use it to judge whether the trade has enough buffer for normal volatility and whether the cash you have set aside is enough to keep the position open.
How to Use the Inputs
- Enter the stock price and number of shares you want to buy on margin.
- Set the initial margin percentage (50% is the Reg T standard).
- Set the maintenance margin percentage (25% is the FINRA minimum).
- Add the margin interest rate and expected holding period.
- Review the margin call trigger price and how far the stock can drop.
- Check the scenario table to see margin calls at different price levels.
Formula used
Margin Call Price = Loan / (Shares ร (1 โ Maintenance Margin %))
Equity = Position Value โ Loan
Equity Ratio = Equity / Position Value ร 100
Leverage = Total Position / Equity
Interest = Loan ร Rate ร (Days / 365)Example Calculation
Result: Margin call at $66.67
You buy 200 shares at $100 = $20,000 position. With 50% margin, you put up $10,000 and borrow $10,000. Margin call triggers when equity drops to 25%: $10,000 / (200 ร 0.75) = $66.67.
Tips & Best Practices
- Set a stop-loss at least 5-10% above the margin call price for safety.
- Higher maintenance margins (broker house rules, not FINRA minimum) shrink your buffer โ check your broker's specific rates.
- Extra cash deposits lower the margin call trigger significantly.
- Interest compounds daily โ factor it into your position sizing.
- Volatile stocks need wider buffers โ a 25% maintenance margin may not be enough.
Margin Buffer
The margin call price is only one part of the picture. Compare it to your planned holding period, the stock's volatility, and any dividend or borrow cost that could change the account balance.
Risk Control
A wider cash buffer or a smaller position size lowers the chance of a forced liquidation. If the trigger price is too close to the current market price, the position is probably too large for the account.
Practical Check
Revisit the maintenance margin and interest assumptions before placing the trade. Small changes in those inputs can move the call level enough to change the decision.
Sources & Methodology
Last updated:
Methodology
This worksheet models a long stock purchase financed partly with broker margin. It calculates starting equity as the selected initial-margin percentage of the position plus any extra cash deposit, loan amount as position value minus equity, and the margin-call trigger price as Loan / (Shares x (1 - Maintenance Margin)). The scenario table then recomputes position value, equity, equity ratio, and any shortfall to the maintenance requirement across a fixed range of stock-price moves.
The interest output is shown separately as simple accrued loan cost over the selected holding period. It does not feed back into the trigger price or model broker-specific house-margin changes, portfolio margin, short sales, or liquidation timing.
Sources
- Understanding Margin Accounts (Investor.gov) โ SEC investor bulletin describing margin borrowing, Regulation T, and maintenance-margin risk.
- Margin Call (Investor.gov) โ Glossary definition of a margin call and how it is triggered.
- Know What Triggers a Margin Call (FINRA) โ FINRA investor guidance covering minimum and house maintenance requirements.
Frequently Asked Questions
Your broker demands you deposit additional funds or sell securities to restore your equity ratio above the maintenance margin. If you don't act, the broker can liquidate positions without notice.
FINRA requires 25% minimum, but most brokers set higher house requirements (30-40%). Check your broker's specific requirements.
Yes. If the stock drops enough, your losses can exceed your initial investment because you still owe the broker for the loan.
Extra cash beyond the initial margin increases your equity, lowering the margin call trigger price and giving you a larger safety buffer. That additional equity can be the difference between a normal drawdown and a forced sale.
Most brokers charge daily interest on the outstanding loan balance, calculated as: Loan ร Annual Rate ร (Days / 365). The longer you hold the position, the more the loan cost reduces your net result.
Set a stop-loss above the margin call price, maintain excess equity, or use less leverage. Monitor your equity ratio daily.
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