Getting Started

Configure your simulation with these settings:

• Trading Mode:
  • Simulation Mode: AI simulates price movements using Monte Carlo. Great for learning.
  • Paper Trading Mode: You enter real prices manually each month. Practice with real market data.
• Starting Capital: Your initial cash balance (AUD)
• Start Date: When your simulation begins (defaults to current month)
• Marginal Tax Rate: Your income tax bracket for capital gains calculations
• Brokerage Fees: Flat fees charged per stock trade ($20 default) and per options trade ($35 default)
• Market Volatility: (Simulation mode only) Affects how much prices swing - Low (0.5×), Normal (1×), High (1.5×)

Stock Information

The simulator includes 52 ASX stocks with exchange-traded options across 10 sectors:

Beta and volatility values are fetched from Yahoo Finance for paper trading mode.

Sector Parameters (Simulation Mode)

Each sector has base volatility and trend affecting price movements:

Price Simulation (Simulation Mode)

When you click "Simulate Month & Advance", the backend server calculates new prices using Monte Carlo simulation:

1. 4 weekly price movements are simulated per month
2. Each movement uses a random walk with sector-based drift
3. Volatility = Sector Volatility × Stock Beta × Market Volatility Setting
4. Prices are sent back to the frontend and stored

Note: If the backend is unavailable, a local fallback simulation runs in the browser.

Paper Trading Mode

In paper trading mode, YOU enter the real market prices:

• When advancing months, a modal appears for price entry
• For shares: Enter the last traded price
• For options: Enter the mid-market price (average of bid and ask)
• Click "Update Prices" anytime to update current prices
• Use "Jump to Date" to move forward or backward in time (can only go back to your last trade)

Research Page

Click "Research" to view historical price charts and statistics. The data source depends on mode:

• Paper Trading: Real historical prices from Yahoo Finance (auto-fetched on start)
• Simulation: Monte Carlo generated historical prices

Options Pricing (Black-Scholes)

Option premiums are calculated using the Black-Scholes model:

• Risk-free rate: 4% per annum
• Volatility: Sector volatility × Stock beta
• Time to expiry: Days until 3rd Thursday of expiry month
• Small random noise (±10%) is added for realism

Strike step sizes: $0.50 (price <$10), $2.50 (<$50), $5.00 (<$100), $10.00 (≥$100)

Options Expiry & Exercise

Options expire on the 3rd Thursday of their expiry month. When options expire, you'll see a modal allowing you to choose how to handle in-the-money (ITM) long options:

Long Options (you bought):

• Long Call ITM: Choose to exercise (buy shares at strike - requires cash) or let expire worthless
• Long Put ITM: Choose to exercise (sell shares at strike - requires shares) or let expire worthless
• OTM: Expire worthless automatically - you lose the premium paid

Short Options (you sold):

• Short Call ITM: Automatically assigned - shares called away (covered) or net cash settlement (naked)
• Short Put ITM: Automatically assigned - you buy shares at strike (requires cash) or net settlement
• OTM: Expire worthless - you keep the premium received

Tax Calculations

Tax is assessed at the end of the Australian financial year (June 30). This is simplified and may not reflect actual tax law.

Taxable Events:

• Options gains/losses: Taxed at full marginal rate
• Short-term capital gains (<12 months): Taxed at full marginal rate
• Long-term capital gains (≥12 months): 50% CGT discount, then marginal rate

Tax Mechanics:

• Share sales use FIFO (First In, First Out) for cost basis
• Each purchase lot's date is tracked for holding period
• Net losses carry forward to offset future gains
• If you owe tax but lack cash, you must sell shares
• Brokerage fees are NOT tax deductible in this simulation

Save & Load

Your simulation state can be saved and loaded:

• Save: Downloads a JSON file with all your data
• Load: Restores a previously saved simulation
• Saved data includes: positions, trade history, prices, tax tracking, mode, and settings

Architecture (Docker Deployment)

When running via Docker, the app uses a client-server architecture:

• Frontend (port 3000): Serves the HTML/JS app
• Backend: Handles Yahoo Finance API proxy, price/volatility caching, and Monte Carlo simulation

The backend fetches real market data (prices, beta, volatility) from Yahoo Finance and caches it for 24 hours.

Authentication & Subscription

The simulator offers a 3-month free trial. To continue beyond 3 months:

• Click the Login button in the top-right corner
• Sign in using your preferred identity provider (Google, GitHub, etc.)
• Subscribe to the Pro Plan for just US$24.99/year

Pro Plan Features:

• Unlimited simulation time
• Cloud save & sync across devices
• Real historical price data
• All 20 ASX stocks
• Options trading & strategies
• Tax tracking & reporting
• Save & load simulations
• Cancel anytime

Coupon Codes:

Have a coupon code? Enter it in the payment modal to get free months of access!

Note: If Clerk/Stripe are not configured, the app runs in demo mode with unlimited access.