Position Size Calculator for Risk-Based Lot Sizing
Info
The Position Size Calculator for Risk-Based Lot Sizing is a Script for MetaTrader 5 that run the script on the chart of the symbol you plan to trade. Enter your risk tolerance, either as a percentage of your account equity or a fixed amount in your account currency, and specify your stop-loss distance.
Usage
This tool is typically used for enhancing chart analysis and decision making.
Platform
This Script works exclusively on MetaTrader 5 (both build 600+ and newer versions).
Setup
Place the downloaded file in MQL5/Scripts folder via File ? Open Data Folder in MetaTrader 5.
How to Install and Use Position Size Calculator for Risk-Based Lot Sizing
1. Installation: Move your script file into the MQL/Scripts directory and restart the platform.
2. Execution: Drag the script onto a chart; it will perform a one-time action, such as closing all open orders or clearing chart objects.
3. Editing: Use MetaEditor (F4) to modify code, click "Compile," and verify no errors appear in the terminal before running.
4. Removing: Scripts stop automatically, but you can remove them manually by right-clicking the chart and choosing "Remove Script."
Frequently Asked Questions
Q: How are scripts different from EAs? A: Scripts execute a single action and then stop; EAs monitor the market and trade continuously.
Q: Can I assign a hotkey to a script? A: Yes, right-click the script in the Navigator, select "Set Hotkey," and define your preferred keyboard shortcut.
Q: Why did my script stop? A: Scripts are designed to stop immediately after finishing their programmed command; this is normal behavior.
What this tool does
Run the script on the chart of the symbol you plan to trade.
Typical Use Case
This Script excels in automated trading and technical analysis on MetaTrader 5.
Compatible Platform & Setup
This Script works on MetaTrader 5. Place the file in the MQL5/Scripts folder and restart the terminal.
Description & Settings
Related: Trade Journal Exporter: Closed Positions to CSV - another powerful script for MetaTrader 5 traders.
Run the script on the chart of the symbol you plan to trade. Enter your risk tolerance, either as a percentage of your account equity or a fixed amount in your account currency, and specify your stop-loss distance. This can be in points or a specific price level.Also recommended: set stop loss on all open positions by target loss amount - similar script with strong performance on MetaTrader 5.
The script will then calculate and return the appropriate lot size for your trade.
The calculation is based on the symbol's actual contract specifications, including tick size and tick value for precise monetary calculations. It also uses volume minimums, maximums, and steps to normalize the lot size.
The resulting lot size is rounded down to the nearest volume step. This ensures that your actual risk does not exceed your specified budget. The script will also report the exact risk associated with the normalized lot size.
Additionally, the script estimates the required margin for the planned trade direction using OrderCalcMargin. It provides clear warnings if:
- The position would exceed your available free margin.
- The calculated lot size falls below the symbol's minimum allowed size (meaning even the minimum lot size risks more than your budget).
- The lot size needs to be capped at the symbol's maximum allowed size.
A comprehensive report is provided in the chart's Comment section, the Experts journal, and as a one-line Alert.
This script is compatible with forex pairs, metals, indices, and any symbol with valid contract specifications. It performs calculations only and does not execute any trades.
You may also like: close profit positions: instant exposure management - excellent alternative for script users on MetaTrader 5.
Source Code
#property copyright "RobotFX"
#property version "1.00"
#property description "This code is educational. Feel free to use, modify and upgrade as you wish. Visit ROBOTFX.ORG for professional trading tools"
#property script_show_inputs
enum ENUM_RISK_MODE
{
RISK_PERCENT_EQUITY = 0,
RISK_FIXED_MONEY = 1
};
enum ENUM_SL_MODE.......
⚠ Limitations & Risk Warning
- This tool is provided for educational and testing purposes only.
- Past performance does not guarantee future results.
- Trading involves substantial risk of loss. Use on a demo account first.
- Results may vary depending on market conditions, broker, and settings.
- We recommend thorough backtesting and forward testing before using with real funds.