Updated: 2026-02-20

Free Position Size Calculator for Traders

Enter your account size, risk percentage, entry price, and stop-loss to calculate exactly how many units, shares, or contracts to trade across stocks, options, futures, forex, and crypto. The calculator is free and intentionally simple so you can plan trades quickly without skipping risk logic.

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Position Size Calculator

Enter your account size, risk percentage, entry price, and stop-loss to calculate exactly how many units, shares, or contracts to trade across stocks, options, futures, forex, and crypto.

Note

Outputs are only as accurate as your inputs.

Autopilot recommendation

Personalized sizing from your edge

Uses your historical win/loss profile, Kelly variants, and drawdown constraints.

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20 units

  • >Risk amount: $100
  • >Stop distance: 5 (5%)
  • >Position notional: $2000 (20% of account)

How to Use the Position Size Calculator

Enter your inputs before you place the trade, not after. Pre-trade planning is where calculators create value.

Use realistic values based on your actual execution conditions. If you understate slippage, fees, or stop distance, output quality collapses.

Document the result inside your journal so you can compare planned vs realized outcomes during review.

How Position Sizing Works for Crypto and Futures

Position sizing converts your risk rule into a concrete number of units or contracts. You decide the maximum dollar amount you are willing to lose, then the calculator divides that by the distance to your stop-loss.

For perpetual futures and leveraged positions, this is the starting point — not the final answer. You still need to check that the resulting position fits within your margin, stays clear of your liquidation price, and accounts for fees and funding.

Example: $10,000 account, 1% risk ($100), entry $50,000, stop $49,000. Stop distance = $1,000. Position = 0.1 BTC ($5,000 notional).

  • Risk amount = account size × (risk % / 100)
  • Stop distance = |entry − stop|
  • Position size (units) = risk amount / stop distance
  • Position notional = units × entry price

Why This Metric Matters

Most preventable losses come from skipping one simple calculation when markets move fast. This tool enforces the minimum math needed for disciplined execution.

The value compounds when used consistently. One correct risk decision rarely changes a year; repeated correct decisions usually do.

Tie calculator output to your strategy tags so you can evaluate whether your planning assumptions match live performance.

Add It to Your Weekly Workflow

Use this tool at planning time, then compare outcome quality in weekly review sessions.

If planned and realized values diverge, investigate execution behavior before adjusting strategy logic.

Pair this with one behavior correction each week for compounding improvement.

Common Mistakes

Using unrealistic inputs because they feel better emotionally.

Changing parameters mid-trade to justify staying in a bad position.

Treating one output as a signal to trade rather than a risk filter.

Related Resources

FAQ

?Is this Position Size Calculator free to use?

Yes. The calculator is free and available without signup.

?How do I calculate position size from risk and a stop-loss?

Convert your risk rule into dollars (account size × risk %), then divide by stop distance (|entry − stop|). The result is the number of units you can trade while keeping the stop-out loss near your planned risk amount.

?Does this work for shorts and perpetual futures?

Yes. The calculator uses absolute stop distance, so it works for longs and shorts on any instrument — spot, futures, or perps. For leveraged positions, also check that the sized position stays within your margin and liquidation limits.

?How much should I risk per trade?

Most professional traders risk 0.5% to 2% of their account per trade. Beginners should start at the lower end. The key is consistency: picking a fixed risk percentage and applying it every time prevents one bad trade from doing outsized damage.

?Does position size change with leverage?

The number of units stays the same — leverage only affects how much margin you post, not your dollar risk. However, leverage brings your liquidation price closer to entry, so always cross-check with a liquidation calculator.

?What if my stop distance is very small?

A tight stop produces a larger position size. That can mean high notional exposure relative to your account. If the position notional exceeds your comfort level, either widen the stop or reduce the risk percentage.

?Can I use this for Bitcoin and altcoin trades?

Yes. Enter any crypto's entry and stop-loss prices. The calculator outputs fractional units, so it works whether you are trading 0.01 BTC or 500 SOL. The math is the same for all assets.

?How does this relate to risk-reward ratio?

Position sizing tells you how much to trade. Risk-reward tells you whether the trade is worth taking. Use both: first check that R:R justifies entry, then size the position so the stop-loss costs exactly your planned risk amount.

?How accurate are calculator outputs?

Outputs are only as accurate as inputs. Use realistic assumptions and review planned vs realized values weekly.

?Can Tiltless save these values to my journal?

Yes. You can pair tool outputs with your review workflow and setup tags for better post-trade diagnostics.

Track position-size-calculator with Tiltless

See plans and run one weekly review loop with Tiltless: edges, leaks, and enforceable next actions.

Free Position Size Calculator Calculator (2026) | Tiltless