The most realistic
paper trading platform

Experience real slippage, partial fills, and market impact. Test drive 22 different brokers with their exact rules, all in one platform. Practice with the friction you'll face with real money.

Real order execution with slippage and fees
< 5ms
Execution Latency
100%
Real Market Data
L1 NBBO
Price Feeds
0
Risk to You

The hidden cost of unrealistic practice

When you transition from paper trading to real money, the shock can be devastating. Strategies that worked perfectly in simulation suddenly fail because they never accounted for the messy reality of actual markets.

Fantasy Paper Trading

What most platforms show you

Market Buy 100 AAPL✓ Filled @ $197.60
Limit Sell 500 TSLA @ $350.00✓ Filled Instantly
Stop Loss @ $348.00✓ Perfect Exit
$0.00
P&L Drift
SEC & TAF Fees:$0.00
Slippage Impact:$0.00
Bid-Ask Spread:$0.00
Partial Fill Loss:$0.00
Latency:0ms

"This trading thing is easy!"

Paper Reality

What actually happens in real markets

Market Buy 100 AAPL⚠ Filled @ $197.73 (+$13)
Limit Sell 500 TSLA @ $350.00✗ Partial Fill (310 shares)
Stop Loss @ $348.00✗ Slipped to $346.95
-$368.95
P&L Drift
SEC & TAF Fees:-$8.45
Slippage Impact:-$325.50
Bid-Ask Spread:-$27.00
Partial Fill Loss:-$8.00
Latency:250ms

"Why didn't anyone warn me?"

Paper shows you what trading actually feels like - with all the friction, slippage, and market realities that other platforms ignore.

Built for realistic trading simulation

Every feature designed to mirror real market conditions and prepare you for actual trading. Experience the chaos, complexity, and nuance of real markets without risking a single dollar.

Real-Time Execution Engine

Matching logic based on NBBO, order type, and time priority. Experience realistic fills, not instant perfection. Access via API.

Simulated Market Latency

Add realistic network delays. Test your strategies under different conditions, from retail to HFT scenarios.

Partial Fills & Slippage

Large orders get partial fills based on liquidity. Experience real slippage and price impact modeling.

Market Events & Halts

Trade through halts, circuit breakers, and auction periods. Learn to navigate real market conditions.

Real Margin & Fees

Full margin simulation with interest, calls, and liquidations. Accurate fee modeling including SEC, FINRA, and exchange fees. Learn more.

Real P&L Tracking

Track your realized and unrealized gains with accurate cost basis calculations. See your true performance without the complexity of tax implications.

Industry First

Test drive 22 different brokersbefore you commit

Paper is the only platform that accurately emulates the exact trading rules, restrictions, and behaviors of major brokers. Compare commissions, margin requirements, trading hours, and order types across brokers to find your perfect match.

Live Broker Comparison

FidelityPre-market: 7:00 AM
$0 equity / $0.65 options
Interactive BrokersPre-market: 4:00 AM
$0.005/share / $0.65 options
RobinhoodNo short selling
$0 equity / $0 options
Tastytrade$10 cap per leg
$0 equity / $1 options
Each broker has unique rules that affect your trading strategy and profitability

Why broker emulation matters

Accurate Commission Modeling

Experience exact commission structures including per-share pricing, option contract fees, and broker-specific caps

Trading Hour Restrictions

Fidelity starts pre-market at 7am while IBKR starts at 4am - test how this impacts your strategy

Feature Availability

Robinhood doesn't allow short selling, Vanguard has no extended hours - know before you go

Portfolio Type Support

Test portfolio margin at Schwab, IRA match bonuses at Robinhood, or cash-only at Public

All 22 brokers, perfectly emulated

Interactive Brokers
Fidelity
Charles Schwab
Robinhood
Webull
Vanguard
E*TRADE
Merrill Edge
moomoo
Public.com
TD Ameritrade
Ally Invest
SoFi Invest
Tastytrade
Firstrade
TradeStation
Lightspeed
Cobra Trading
J.P. Morgan
Tradier
Alpaca
Default

Switch between brokers instantly. Test your strategies across different platforms.

More brokers coming soon

Professional Trading Tools

Advanced features the pros actually use

Go beyond basic orders. Paper supports the full spectrum of professional trading strategies and risk management tools you'll find at any major brokerage. Perfect for Pro traders.

Portfolio Margin

Test strategies with professional margin models before risking real capital.

SIMPLEBasic shock-based calculations
SPANCME's risk-based model
TIMSOCC's theoretical pricing

Advanced Order Types

Execute sophisticated strategies with institutional-grade order types.

  • Trailing Stop Orders - Dynamic risk management
  • Bracket Orders - Automated profit & loss targets
  • FOK & IOC - Fill-or-Kill, Immediate-or-Cancel
  • Extended Hours - Pre-market & after-hours trading

See it in action

SIMPLE Risk Engine

Basic shock-based calculation

SIMPLE Risk Engine
// Running SIMPLE margin calculation calculatePortfolioMargin({ engine: "SIMPLE", positions: portfolio.positions, shockPercent: 15, netLiquidation: 50000 }) => Running risk scenarios... => Equity shock: -$7,500 => Margin requirement: $12,500 => Available buying power: $37,500
✓ Calculation complete

Bracket Order Entry

Complete risk management strategy

Bracket Order Entry
// Entering bracket order with targets { "symbol": "NVDA", "type": "LIMIT", "side": "BUY_TO_OPEN", "quantity": 100, "limitPrice": 485.00, "isBracketOrder": true, "profitTargetPrice": 510.00, "stopLossPrice": 465.00, "timeInForce": "GTC" } => Order submitted to matching engine => Parent order: PENDING => Profit target: PENDING_PARENT => Stop loss: PENDING_PARENT
✓ Bracket order staged
First of its kind

Trade with AI agents using natural language

Paper is the first trading platform with Model Context Protocol (MCP) integration. Let AI assistants like Claude execute trades, manage portfolios, and analyze markets through simple conversations. Test the future of AI-driven investing in a risk-free environment.

You:

"Buy 100 shares of Apple and set a stop loss at 5% below the current price"

AI:

"I'll place that order for you. Current AAPL price is $178.50..."

Order placed: BUY 100 AAPL @ Market
Stop Loss set: $169.58 (-5%)
You:

"Show me the best performing sectors in my portfolio"

AI:

"I've analyzed your positions by sector. Technology is up 15.2%..."

Revolutionary AI Trading Features

  • Natural Language Trading

    Describe complex strategies in plain English

  • Autonomous Execution

    AI agents can place, modify, and cancel orders

  • Portfolio Intelligence

    Get AI-powered insights on positions and performance

  • Risk-Free Testing

    Perfect environment to test AI trading strategies

Learn more about AI paper trading with MCP →

Perfect for beginners learning to trade

Start your trading journey in a safe, realistic environment. Learn market mechanics, test strategies, and build confidence without risking real money.

Why beginners choose Paper for paper trading

1
Start free, upgrade when ready

Begin with 5 free trades daily. Perfect for learning basics without any financial commitment.

2
Real market conditions prepare you

Experience slippage, fees, partial fills, and PDT rules now, not when real money is on the line.

3
Test multiple brokers before choosing

Try all 22 broker interfaces to find the one that fits your trading style.

4
AI assistant helps you learn

Use natural language to place trades and get insights. Perfect for beginners.

Beginner-friendly features

  • Simple market and limit orders to start
  • Real-time P&L tracking shows your progress
  • PDT rules enforced - learn proper risk management
  • Cash account simulation - no margin complexity
  • Mobile-friendly interface for trading anywhere
  • API access to build your own tools

Pro tip: Start with our free tier to learn the basics, then upgrade to Pro when you're ready for advanced features like extended hours and margin trading.

Developer API

Build on Paper's infrastructure

Access the same realistic trading engine through our paper trading API. Perfect for building trading bots, testing algorithms, or integrating paper trading into your platform. Free tier available.

  • REST API

    Place orders, manage portfolios, access market data

  • SSE Streaming

    Real-time order updates via Server-Sent Events

  • MCP Protocol

    Enable AI agents to trade on your behalf

  • Native SDKsComing Soon

    Python, JavaScript, and Go client libraries

Learn more about our paper trading API →

// Place a realistic market order
const API_KEY = 'your_api_key';

const response = await fetch('/api/oms/orders', {
  method: 'POST',
  headers: {
    'X-API-Key': API_KEY,
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    customerId: '550e8400-e29b-41d4-a716-446655440000',
    portfolioId: '660e8400-e29b-41d4-a716-446655440001',
    assetClass: 'EQUITY',
    symbol: 'AAPL',
    side: 'BUY_TO_OPEN',
    quantity: 100,
    type: 'MARKET',
    timeInForce: 'DAY',
    latencyProfile: 'COLOCATED'
  })
});

const order = await response.json();
console.log(`Filled at: $${order.averageFilledPrice}`);
console.log(`Slippage: ${order.executionQuality?.averageSlippagePercent}%`);

Choose your trading plan

Start with our free tier or unlock advanced features for serious traders

Basic

Perfect for getting started

$0/month
  • 5 trades per day
  • Market & limit orders
  • Day or GTC orders
  • 1 portfolio (cash)
  • API & MCP access
  • Portfolio margin (SIMPLE, SPAN or TIMS)
  • Latency simulation (retail only)
  • Extended hours trading
Most Popular

Pro

For serious traders

$20/month
  • Unlimited trades
  • All advanced order types
  • Day, GTC, GTD, FOK, or IOC orders
  • 3 portfolios (cash, margin & IRA)
  • API & MCP access
  • Portfolio margin (SIMPLE, SPAN or TIMS)
  • All latency profiles
  • Extended hours trading

Commercial

For businesses & institutions

$500+/month
  • Everything in Pro
  • 500 accounts included
  • $1 per additional account
  • Priority support
  • Custom latency profiles
  • White-label API
Contact sales

The difference is in the details

Stop practicing in fantasy land. Start training in market reality.

FeatureOther PlatformsPaper
Order ExecutionInstant fills at displayed priceNBBO matching with queue position
Slippage & ImpactNo slippage modelingVolume-aware slippage & market impact
Market ConditionsAlways availableHalts, auctions, market hours
Fee StructureSimplified or no feesSEC, TAF, exchange, regulatory fees
Margin CalculationsBasic buying powerReg T & portfolio margin (SIMPLE, SPAN, or TIMS risk engine)
Broker EmulationGeneric rules only22 brokers with exact rules & restrictions

Frequently asked questions

Everything you need to know about paper trading with Paper

What is paper trading and why use Paper?

Paper trading is practicing stock trading without real money. Paper is the most realistic paper trading platform because we simulate actual market conditions including slippage, partial fills, SEC fees, and broker-specific rules. Unlike other platforms that give you perfect fills at displayed prices, we show you what really happens when you trade.

How does Paper's broker emulation work?

We've analyzed and implemented the exact trading rules, commission structures, margin requirements, and trading hours for 22 different brokers. When you select a broker in Paper, you experience their specific features and limitations - from Robinhood's no short selling to Interactive Brokers' 4am pre-market start. This helps you choose the right broker before opening a real account.

Is Paper really free for paper trading?

Yes! Our Basic plan is completely free and includes 5 trades per day, market/limit orders, and API access. This is perfect for beginners learning to trade. Our Pro plan ($20/month) unlocks unlimited trades, all order types, portfolio margin, and extended hours trading for serious traders who want the full experience.

What is MCP and AI paper trading?

Model Context Protocol (MCP) allows AI assistants like Claude to interact with Paper's API using natural language. You can say "Buy 100 shares of Apple" or "Show me my best performing sectors" and the AI will execute trades and analyze your portfolio. Paper is the first trading platform with MCP support, making it perfect for testing AI-driven trading strategies risk-free.

Can I use Paper for day trading practice?

Absolutely! Paper is ideal for day trading practice. We simulate PDT (Pattern Day Trading) rules, real-time executions with proper queue positioning, and accurate intraday buying power calculations. Our platform tracks your day trades and warns you about PDT violations just like a real broker would. Plus, you can practice with different latency profiles to match your internet speed.

Do you support options paper trading?

Options paper trading is coming soon! We're building the most realistic options trading simulator with proper Greeks calculation, IV modeling, and assignment simulation. Join our waitlist to be notified when options trading launches. In the meantime, you can practice stock trading with all the advanced order types that options traders use.

How accurate is your paper trading simulator?

Extremely accurate. We use real-time NBBO data, simulate actual queue positioning for limit orders, model slippage based on order size and liquidity, and include all regulatory fees (SEC, TAF, exchange fees). Our execution engine considers bid-ask spreads, market depth, and even simulates partial fills for large orders. This is why professional traders use Paper to test their strategies.

Can I connect Paper to my trading algorithms?

Yes! Paper provides a comprehensive REST API and Server-Sent Events (SSE) for real-time updates. You can place orders, manage portfolios, and access market data programmatically. We're also launching native SDKs for Python, JavaScript, and Go. Our API is perfect for testing trading bots, backtesting strategies, or integrating paper trading into your own platform.