Calculators
The sums that come before a trade or an investment, each printed line by line so you can check the arithmetic and see which input moves the answer most.
Margin & Leverage
- Margin Call Calculator
The share price that triggers a margin call on a long or short position, from your loan and the maintenance requirement.
Background: maintenance margin
- Margin Interest Calculator
Interest on a margin loan by the day, the month and the holding period, and the return a trade needs to cover it.
Background: margin interest
- Leverage Calculator
Your leverage ratio from equity and position value, and what a given market move does to your equity.
Background: the leverage ratio
Risk Management
- Loss Recovery Calculator
The gain needed to get back to even after a loss, and the balance after a run of losing and winning trades.
Background: maximum drawdown
- Position Size Calculator
Shares from your account risk and stop, the reward in R, and the loss if the stock opens past the stop.
Background: the reward-to-risk ratio
Options
- Options Break-Even Calculator
Break-even price, maximum loss and profit at a target for a bought or sold call or put.
Background: option break-even prices
Dividends
- Dividend Income Calculator
Yearly dividend income and yield on cost, and what is left after margin interest when the shares are bought with a loan.
Background: return of capital
Earnings
- Profit Margin Calculator
Gross, operating and net margin from an income statement, and earnings per share from the share count.
Background: operating leverage
Before you trust an output
Every calculator runs in your browser and sends nothing anywhere. The answers are only as good as the inputs, and the inputs that matter most are the ones you have to look up or estimate: your broker's house maintenance requirement, the margin rate on your statement, where your stop really belongs. A calculator will turn a guess into a number with two decimal places without complaint.
Change one input at a time and watch the output. If raising the maintenance requirement by five points moves your margin call price a long way toward today's price, or a slightly wider stop halves the share count, that sensitivity is the useful result, because it tells you which number deserves the most checking.