Calculators that show you the uncomfortable bit
Most calculators give you a number. These show you the thing the number is hiding: that a 50% loss needs a 100% gain, that a 1% fee eats a quarter of your pot, and that a genuine edge still ruins you if you bet too much. Free to use, free to embed.
Compound interest calculator
Set a monthly contribution, a return and a horizon, and watch the curve bend. Free, no signup, and it shows you the thing most calculators hide.
Risk of ruin calculator
Set a win rate above 50%, so you have a genuine edge. Then push the bet size up and watch how reliably a positive edge still ends in ruin.
DCF fair value calculator
Earnings, growth and an exit multiple. See the price path and the annual return your assumptions actually imply.
Drawdown recovery calculator
How far you fell, and the gain required to get back to level. The asymmetry is brutal and it is arithmetic.
Fund fee impact calculator
A 1% annual fee sounds trivial. Compounded over a working lifetime it is not. See the gap for yourself.
Inflation calculator
What your money buys later, at a given rate of inflation. Cash is not the safe option; it is the certain one.