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RISK MANAGEMENT

Position Size Calculator

The most important calculation in trading. Determine exactly how many lots to risk so you never exceed your loss limit.

Trade Parameters

Your total capital available for trading

1%
Conservative (0.5%)Aggressive (5%+)

In pips (e.g., 20 pips)

Risk Metrics

Max losses before ruin

100

consecutive trades
Pip/point value

$10

per standard lot
Amount at Risk$100

This is the maximum you can lose on this trade

Position Size
Standard Lots0.50
Mini Lots5.0
Micro Lots50
1 Standard Lot = 100,000 base currency units

Important: Always verify with your broker

Pip/point values may vary depending on your broker, your account currency, and market conditions. This calculator uses standard values for a USD account. If your account is in a different currency, adjust accordingly.

The Complete Guide to Position Sizing

The art and science of sizing your trades to survive and thrive

Imagine two traders with exactly the same strategy, the same starting capital, and the same market conditions. After one year, one has doubled their account, the other has lost it. The only difference? Position sizing.

Position size calculation is probably the most underestimated concept in trading. Beginners spend hours looking for the best indicator, the best entry strategy, the best time to trade... but completely neglect the "how much" -- which is infinitely more important than the "when".

This guide will transform you from a trader who "guesses" their position size to one who calculates it scientifically. By the end, you will understand why Van Tharp, legendary trading coach, said: "Position sizing is responsible for 90% of the variation in performance between traders."

The Position Sizing Formula

The Universal Formula

Size = Risk ($) ÷ (SL × Value/Point)
Risk ($)

Capital × % Risk per trade

Ex: 10,000$ × 1% = 100$

SL (Stop Loss)

Distance in pips or points

Ex: 25 pips on EUR/USD

Value/Point

Monetary value of a pip/point

Ex: $10/pip for 1 lot EUR/USD

Concrete Step-by-Step Example

1

Determine your risk in dollars

Capital: $25,000 | Risk: 2% → $500 at risk

2

Identify your stop loss

Technical analysis indicates SL at 40 pips from entry price

3

Find the pip value

EUR/USD with USD account: $10/pip per standard lot

4

Apply the formula

Size = $500 ÷ (40 pips × $10/pip)

Size = $500 ÷ $400

Size = 1.25 lots

Why Position Sizing Is Critical

Here is a mathematical truth that few traders understand: a 50% loss requires a 100% gain to get back to breakeven. Not 50%. 100%.

The Cruel Mathematics of Drawdowns

LossGain required to recoverDifficulty
10%11%Easy
20%25%Moderate
30%43%Difficult
50%100%Very Difficult
75%300%Nearly Impossible
90%900%Game Over

This is why pros limit their risk to 0.5-2% per trade. Even 10 consecutive losses (rare but possible) won't wipe them out.

Trader A: 10% Risk

Capital: 10,000$

Risk: $1,000 per trade

5 consecutive losses:

Trade 1: 10,000$ → 9,000$

Trade 2: 9,000$ → 8,100$

Trade 3: 8,100$ → 7,290$

Trade 4: 7,290$ → 6,561$

Trade 5: 6,561$ → 5,905$

-41% drawdown

Need +69% to recover

Trader B: 1% Risk

Capital: 10,000$

Risk: $100 per trade

5 consecutive losses:

Trade 1: 10,000$ → 9,900$

Trade 2: 9,900$ → 9,801$

Trade 3: 9,801$ → 9,703$

Trade 4: 9,703$ → 9,606$

Trade 5: 9,606$ → 9,510$

-4.9% drawdown

Need only +5.2% to recover

Position Sizing Methods

Fixed % of Capital

RECOMMENDED

Always risk the same percentage (e.g., 1%) on every trade. This is the method used by this calculator.

Simple and consistent
Automatically adapts to capital
Protects against ruin

Fixed Amount ($)

SIMPLE

Always risk the same dollar amount (e.g., $100) per trade, regardless of capital.

Very easy to calculate
Does not adapt to capital
Can become too risky or too conservative

Kelly Criterion

ADVANCED

Calculates optimal size based on your win rate and risk/reward ratio.

Mathematically optimal
Maximizes long-term growth
Very volatile (use Half Kelly)
Calculate my Kelly

ATR-Based

DYNAMIC

Adjusts size based on market volatility (ATR - Average True Range).

Adapts to volatility
Natural and logical stop loss
More complex to set up

What Risk for Your Profile?

Prop Firm Trader

Funded account with strict drawdown rules

Recommended risk

0.25% - 0.5%

With 10% max DD, you can absorb 20-40 consecutive losses. This is your life insurance.

Swing Trader

Trades lasting several days to weeks

Recommended risk

1% - 2%

Wider stop losses = fewer trades = can afford slightly more risk per position.

Scalper / Day Trader

Many intraday trades

Recommended risk

0.25% - 0.5%

Many trades = high cumulative risk. Stay ultra conservative per position.

The 6 Fatal Position Sizing Errors

#1 Risking a % of remaining capital

If you recalculate after each loss, you can technically never reach zero, but you will be stuck with a tiny capital. Use a fixed % or recalculate monthly.

#2 Ignoring correlation

3 open trades on EUR/USD, GBP/USD and AUD/USD? You don't have 3 positions at 1% - you effectively have 1 position at 3% on the dollar.

#3 Averaging down

Doubling your position on a losing trade doubles your risk. This is how 5% drawdowns become 50% catastrophes.

#4 Forgetting slippage

In volatile conditions, your stop loss can be executed well beyond your price. Allow for a 5-10% margin on your risk calculation.

#5 Increasing after wins

Post-win euphoria pushes traders to oversize. The next loss will be even more devastating. Maintain constant discipline.

#6 Using maximum available leverage

Just because you have 100:1 leverage doesn't mean you should use it. Leverage is a tool, not a goal. Always calculate in real risk terms.

Detailed Practical Scenarios

Scenario 1: Classic Forex Trade

You identify a long setup on GBP/USD. Your technical analysis places the stop loss below the last swing low, at 35 pips from your entry.

Capital15,000$
Chosen risk1.5%
Stop Loss35 pips
Pip value (GBP/USD)10$/pip/lot

// Calculation

Risk = $15,000 × 1.5% = $225

SL Cost = 35 × $10 = $350/lot

Size = $225 ÷ $350

= 0.64 lots (6.4 mini lots)

Scenario 2: Gold Trade (XAU/USD)

Short setup on gold after a resistance rejection. Stop loss at 800 pips ($8.00) above entry.

Capital50,000$
Chosen risk1%
Stop Loss$8.00 (800 pips)
Pip value (Gold)1$/pip/lot

// Calculation

Risk = $50,000 × 1% = $500

SL Cost = 800 × $1 = $800/lot

Size = $500 ÷ $800

= 0.625 lots

Scenario 3: Scalp on US30 (Dow Jones)

Quick scalp on the Dow Jones index. Tight stop loss at 25 points.

Capital25,000$
Chosen risk0.5%
Stop Loss25 points
Point value (US30)1$/point/contract

// Calculation

Risk = $25,000 × 0.5% = $125

SL Cost = 25 × $1 = $25/contract

Size = $125 ÷ $25

= 5 contracts

Frequently Asked Questions (FAQ)

How do I find the exact pip value for my broker?

Each broker provides this information in the contract specifications. The value depends on your account currency, the pair traded, and lot size. For a USD account on XXX/USD pairs, it's typically $10/pip for 1 standard lot. If in doubt, make a micro test trade or contact your broker.

Should I include commissions in my risk calculation?

Yes, ideally. Purists subtract commissions from their 'amount to risk'. If you risk $100 and commissions are $5, calculate with $95. In practice, if your commissions are < 5% of your risk, the impact is negligible.

What if the calculator gives a result with many decimal places?

Always round DOWN. If the result is 1.37 lots, trade 1.3 lots. It's better to slightly under-risk than to over-risk. Some brokers accept micro-lots (0.01), others only mini-lots (0.1).

My stop loss is very wide, the position size is tiny. What should I do?

That's the calculation doing its job! A wide stop loss requires a small position to keep risk constant. If the position is too small to be practical (<0.01 lot), you have three options: reduce the stop loss, increase your risk (not recommended), or skip this trade.

Should I recalculate my position size after every trade?

For the fixed %: recalculate on each trade based on your current capital. This creates a 'compound growth' effect on your gains and limits losses during difficult periods. Some traders prefer recalculating monthly for simplicity.

How to manage multiple open positions simultaneously?

Add up your risks. If you have 3 positions at 1% each, your total risk is 3%. For correlated assets (e.g., multiple USD pairs), treat them as a single position. Many traders limit their total open risk to a maximum of 5-6%.

Does position sizing change based on timeframe?

The calculation remains identical, but the implications differ. In scalping, you'll make more trades so your cumulative daily risk will be higher -- use a lower % per trade. In swing trading, fewer trades allow a slightly higher % per position.

How to adjust for weekend gaps?

Positions held over the weekend are exposed to gap risk. Options: 1) Close your positions on Friday, 2) Reduce your size by 50% if you keep the position, 3) Widen your stop loss (but recalculate the size accordingly).

Conclusion: The Calculation of Survival

Position sizing isn't sexy. It's not a revolutionary indicator, not a secret strategy, not a miracle bot. It's just simple mathematics. But it's precisely what separates traders who survive from those who blow up.

Remember the golden rule: your number one goal is to survive. Not to get rich tomorrow. Not to double your account this month. Just survive long enough for your edge to manifest.

The three principles to remember:

  1. Calculate BEFORE entering -- Never during, never after. Position size is determined at the same time as technical analysis.
  2. Be conservative -- If you're torn between 1% and 2%, choose 1%. You'll never regret under-risking.
  3. Be consistent -- Don't increase your risk after a winning streak, don't reduce it (or stop trading) after a losing streak.

Use this calculator religiously before every trade. Make it a reflex. The day you are tempted to "take a big trade" because you are "sure of yourself," this calculation will save you.

Complete Your Risk Management Arsenal

Position sizing is the first step. Use our other tools to optimize your risk management and maximize your chances of success.