Trading Calculators
The glossary explains what things are and the how-to guides are procedures. These are the arithmetic — the numbers you need before a decision rather than after it.
Every calculator here shows its working. The formula is on the page, the worked example runs it by hand, and the failure section says where the number stops being reliable. A calculator that gives you a figure and hides how it got there is asking for more trust than it has earned.
Nothing you type leaves your browser. There is no account, no saving, and no request sent anywhere — the arithmetic runs on your own machine, and the page works with JavaScript switched off.
Expectancy Calculator
the average result of one trade, in R
Fee Drag Calculator
what an annual charge removes from a pot over decades
Leverage Decay Calculator
how far a leveraged return falls short of the simple multiple
Margin Call Calculator
the price at which your broker liquidates the position
Pip Value Calculator
what one pip is worth at your position size
Portfolio Heat Calculator
your total open risk, adjusted for how correlated the positions are
Tick Value Calculator
what one tick is worth and how many contracts your risk allows
7 calculators written so far. Educational, not financial advice.