🧮 Free Trading Tool

Position Size &
Risk/Reward Calculator

Calculate the exact lot size to risk a fixed percentage of your account on every trade — the single most important habit for surviving as a trader long enough to become profitable.

Forex (standard lot)
Gold (XAUUSD)
Index (e.g. US100, US30)
Crypto (e.g. BTCUSD)

Pip values are approximations for a standard lot. Always confirm exact pip/point value with your broker before sizing a live trade.

Amount at risk$100.00
Recommended lot size0.50
Potential loss (if stopped out)-$100.00
Potential profit (at target R:R)+$200.00

Why Position Sizing Matters

Most new traders lose money not because their strategy is bad, but because their position size is wrong. Risking too much on a single trade turns a normal losing streak — something every strategy has — into an account-ending event.

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The 1% Rule

A widely used guideline among professional and prop firm traders is to risk no more than 1% of account equity on any single trade (some tighten this to 0.5% for higher-volatility instruments like gold or indices). At 1% risk per trade, a string of 10 consecutive losses — statistically possible even with a good strategy — only costs about 10% of the account, which is recoverable. At 5% risk per trade, the same losing streak wipes out nearly 40%.

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How Lot Size Is Calculated

Divide your dollar risk amount by your stop-loss distance multiplied by the pip/point value of one lot. This guarantees that no matter how wide or tight your stop loss is, the dollar amount you lose if it's hit stays constant at your chosen risk percentage. The lot size is the output of the risk calculation, not an input you guess.

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Why Risk:Reward Ratio Matters

A 1:2 risk:reward ratio means your target profit is twice your risked amount. With this ratio, a trader only needs to win 34% of trades to break even, and anything above that is profit — which is why many profitable traders have win rates well under 50%.

Common Position Sizing Mistakes

Using the same lot size on every trade regardless of stop-loss distance
Increasing position size after a losing streak to "win it back" faster
Not accounting for correlated positions (e.g. two long USD pairs) that compound the same risk
Ignoring spread and commission when calculating true breakeven
Sizing based on how confident you feel about a setup instead of a fixed rule
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