Margin Call Price Calculator (Buying Shares on Margin)
The share price at which a broker will demand more money when you buy on margin, how far that is from your purchase price, and what a price move does to your own money.
Results
The dashed line marks the value you entered.
What this tool does
Buying on margin means borrowing part of the purchase, so a price fall hits your equity harder than the fall itself: with half of the purchase borrowed, a 10 % drop loses 20 % of your money. The broker requires your equity to stay above a maintenance percentage of the position's value; the price at which it falls to that level is the margin call price, found by setting (value − loan) ÷ value equal to the maintenance margin. The result ignores interest on the loan, which keeps adding to what you owe, and brokers can set stricter requirements than the usual minimum.
Formula
margin call price = purchase price × (1 − initial margin) ÷ (1 − maintenance margin) · result on own money = price move ÷ initial margin
Variables
| Symbol | Meaning | Unit |
|---|---|---|
sh | Number of shares bought | — |
p | Purchase price per share | — |
im | Initial margin (the share you pay with your own money) | % |
mm | Maintenance margin (minimum equity the broker requires) | % |
mv | Price move to test | % |
MC | Price at which you get a margin call | — |
FL | Fall from the purchase price that triggers it | % |
LN | Amount borrowed | — |
OW | Your own money | — |
LV | Leverage (position ÷ own money) | — |
RS | Result on your own money for that move | % |
Worked example
- Number of shares bought100
- Purchase price per share50
- Initial margin (the share you pay with your own money)50 %
- Maintenance margin (minimum equity the broker requires)25 %
- Price move to test-10 %
- Price at which you get a margin call33.33
- Fall from the purchase price that triggers it33.3 %
- Amount borrowed2500.00
- Your own money2500.00
- Leverage (position ÷ own money)2.00
- Result on your own money for that move-20.0 %
Limitations
- This is an informational calculator, not personalised financial advice. Rates, fees, taxes and contract conditions vary between institutions and countries.
- The result is an estimate based only on the values you type. Real situations often include factors this calculator does not know about.