No signup required
Free trading calculators.
Standalone, these are one-off calculations that forget you the moment you close the tab. Connected to your real account, the WTP Engine, and your journal, the very same tools turn into a system that remembers, reasons, and coaches.
Risk Sizer
Type your account and stop, get a share count.
Sizes off your real balance in one click, then builds the scale-out ladder and trailing stop you never set yourself, and logs the trade to your journal.
Kelly & Expectancy
Enter a win rate and payoff to get a number.
Pulls your real win rate from your logged trades. The platform knows your edge, so you stop guessing it.
Options Profit Calculator
Model any strategy by hand.
Goes live: the WTP Engine reads the chain and compares strikes and expirations by implied-volatility richness, beside your charts.
103 pro indicators
Free ThinkorSwim indicators, premium when you're ready.
At launch, 31 become free downloads for ThinkorSwim users. Members unlock the full premium library and save 30%.