Calculators & Tools
25 free interactive calculators, simulators and learning games for trading, investing and risk management. They run right in your browser, with no sign-up. The range goes from position sizing, the Kelly criterion and Monte Carlo simulation to a candlestick quiz. Each tool illustrates a concept with example numbers; none of them tells you what to buy or sell.
Trading Backtest Playground (Moving Average Crossover)
Free backtest playground: test a moving average crossover strategy on synthetic price data in your browser, no code needed, and compare it with buy & hold.
Open tool →Black-Scholes Option Calculator with Greeks
Black-Scholes option calculator: theoretical price of European calls and puts with delta, gamma, theta and vega, plus a payoff chart at expiration.
Open tool →Bubble Timing Game: Sell Before the Crash
In the Bubble Timing game the price climbs parabolically. Sell before the bubble bursts: a playful lesson in greed and market timing. Free, in your browser.
Open tool →Bull vs. Bear: Chart Prediction Game
Bull vs. Bear is a free prediction game: guess whether the next candle rises or falls, and see how little a chart alone tells you. Runs in your browser.
Open tool →CAGR Calculator: Calculate Annualized Return
Free CAGR calculator: enter a starting value, an ending value and the period to get the compound annual growth rate, the total return and the doubling time.
Open tool →Candlestick Quiz: Recognize Candlestick Patterns
The Candlestick Quiz tests your knowledge of classic candlestick patterns: hammer, doji, engulfing, marubozu and more. Core technical analysis as a quiz.
Open tool →Chart Pattern Quiz: Head and Shoulders, Flags & More
Train your eye for classic chart patterns in this free quiz: head and shoulders, double top, flag, triangle and more. No sign-up, runs in your browser.
Open tool →Compound Growth Calculator with Monthly Contributions
Free compound growth calculator: see how starting capital, a monthly return and monthly contributions compound over time, with a chart of paid-in vs. gain.
Open tool →Correlation and Diversification Calculator
See how correlation and weighting change the volatility of a two-asset portfolio. A live scatter plot shows why diversification can lower risk.
Open tool →Dividend Calculator: Dividend Income and the Snowball Effect
Model the dividend snowball: reinvested dividends, dividend growth, price growth and monthly contributions over the years, as a simple pre-tax model.
Open tool →Drawdown Recovery Calculator: What Gain Offsets a Loss?
Losses and recoveries are not symmetric: a 50% loss needs a 100% gain to break even. See the gain your drawdown requires and an estimated recovery time.
Open tool →Drawdown Survival: The Risk Management Game
Drawdown Survival: choose your risk per trade and get through 40 trades with a small edge without wrecking your account. A free lesson in position sizing.
Open tool →ETF Savings Plan Calculator with TER Fees and Inflation
Free ETF savings plan calculator: see what a monthly plan could be worth after fund costs (TER) and inflation, in nominal and real terms, year by year.
Open tool →Kelly Criterion Calculator with Growth Simulation
Free Kelly criterion calculator: see the theoretical growth-optimal bet size per trade and compare full, half and quarter Kelly in a live growth simulation.
Open tool →Leverage Calculator: Liquidation Price for CFDs and Crypto
Free leverage and liquidation calculator: from margin, leverage, entry price and maintenance margin, see the liquidation price and your buffer, long or short.
Open tool →Margin Call Game: Feel the Risk of Leverage
In the Margin Call game you pick your leverage and try to survive 30 volatile ticks without being liquidated. How much leverage can you survive?
Open tool →Monte Carlo Simulator for Trading Strategies
Free Monte Carlo simulator for trading strategies: run hundreds of random trade sequences and see percentile bands, drawdown distribution and risk of ruin.
Open tool →News Trader Game: Trading the Headlines
News Trader: read a headline and go long or short before the price moves. Ten rounds show how often the news is already priced in. Free, in your browser.
Open tool →Portfolio Challenge: Test an Asset Allocation
Portfolio Challenge: split 100% across stocks, bonds, gold and crypto, then a random market scenario hits your mix. Diversification you can try out.
Open tool →Position Size Calculator: How Much to Risk per Trade
Free position size calculator: enter account size, risk per trade, entry and stop-loss to see how many units fit your risk limit and what the position is worth.
Open tool →Random or Trend? Spot the Random Walk
Random or trend? Each round, guess whether the price chart has real structure or is a pure random walk. It is much harder than it looks. Free, in your browser.
Open tool →Risk-Reward Ratio Calculator: Break-Even and Expected Value
Free risk-reward calculator: from entry, stop-loss and target, get the risk-reward ratio, the win rate you need to break even and the expected value per trade.
Open tool →Sharpe, Sortino and Calmar Ratio Calculator
Calculate the Sharpe, Sortino and Calmar ratios from annual return, volatility, downside volatility and maximum drawdown, with a rough rating scale.
Open tool →Spike Trader: The Trading Reaction Game
Spike Trader: the price moves live, you go long or short and close at the right moment. 45 seconds, one P&L score and a free lesson in luck versus skill.
Open tool →Tilt Test: How Disciplined Is Your Trading?
The Tilt Test puts you in eight scenarios: follow your plan, take a break or go for a revenge trade. At the end you get your discipline score. Free online.
Open tool →Want to turn your own rule-based strategy into tested, automated software? Learn more about trading bot development.