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Units: 0
Sizing: 0 lots
The Forex Position Size Calculator helps you size trades based on risk, not guesswork. Instead of using the same lot size for every trade, it adjusts position size so your risk stays consistent even when the stop-loss distance changes.
This is one of the most important tools for long-term consistency. When position size matches your risk plan, drawdowns become more controlled and performance tracking becomes more meaningful.
Why Traders Use a Position Size Calculator
Two trades can have the same setup quality but very different stop distances. If you trade the same lot size for both, you are not risking the same amount. A position size calculator fixes this by linking size to the stop-loss and the amount you are willing to risk.
It is also a practical way to reduce emotional decision-making. When the numbers tell you the correct size, you are less likely to oversize a trade out of confidence or undersize it out of fear.
Common Use Cases
- Risk-per-trade rules: keep risk consistent, such as 1% or 2% per trade.
- Fixed-dollar risk: size trades by risking a specific cash amount instead of a percentage.
- Different stop-loss widths: stay consistent whether your stop is 20 pips or 120 pips.
- Cross-pair sizing: compare trades across pairs while keeping account risk stable.
- Scaling plans: decide how much to add without breaking the original risk limit.
What the Inputs Mean
Currency pair and account currency define how pip value will be converted into your account terms. This is important because pip value can change depending on the instrument and currency relationships.
Account balance is the reference point for percentage-based risk. It allows you to keep risk proportional to your equity as your balance grows or declines.
Risk ratio (%) or money lets you choose whether you want to risk a percentage of your balance or a fixed cash amount. Both approaches can be valid depending on your strategy and discipline.
Stop-loss (pips) is the most important sizing input. A wider stop requires a smaller position to keep risk constant, while a tighter stop allows a larger position for the same risk.
Exchange rate helps convert pip value into your account currency so the size calculation reflects your real risk.
How to Interpret the Results
Units shows the position size in base currency units. This is useful if your broker supports unit-based sizing rather than lots.
Sizing (lots) expresses the same value in lots, which is what many forex platforms use for order size. This is the number you typically use when placing a trade.
The key takeaway is that the output is tied directly to your risk and stop-loss. If you widen the stop, the calculator should reduce the lot size, and if you tighten the stop, it should increase the lot size.
Tips for More Consistent Risk Management
Use a stop-loss that makes sense for your strategy first, then let the calculator set the trade size. Many traders do this in reverse, placing a stop that is too tight just to justify a larger lot size.
If you scale into trades, plan sizing in advance. Adding to a position can increase total risk beyond the intended limit if you do not recalculate.
- Keep risk stable: avoid increasing risk after a winning streak or decreasing it after a loss without a plan.
- Match sizing to volatility: wider stops in volatile markets should naturally lead to smaller sizes.
- Account for costs: spreads and commissions can slightly increase effective risk, especially on short stops.