You open your MT5 terminal and wonder how much to risk on the next setup. An MQL5 risk per trade script removes the guesswork by calculating the correct lot size from your stop-loss distance and chosen risk percentage.
- Calculate lot size automatically from stop-loss and risk percent
- Apply the same risk rule to every trade you run
- Attach the script to any chart before placing orders
- Combine it with EAs that already include position sizing
Why Position Sizing Matters on Every Trade
You place a trade with a 50-pip stop and decide the lot size by feel. Two days later the stop is hit and the loss feels larger than expected. A simple MQL5 risk per trade script fixes this by turning your risk percentage into an exact lot size before you click buy or sell.
How the Calculation Works Inside MT5
The script asks for three inputs: account balance, risk percentage, and stop-loss distance in pips. It then divides the risked amount by the pip value of one lot to return the correct trade size. You attach it once, enter the numbers, and the lot size appears in the trade dialog.
Step-by-Step Script Attachment
- Open the Navigator in MT5 and locate the script file
- Drag it onto the chart you plan to trade
- Fill in your risk percentage, usually between 0.5 and 2 percent
- Enter the stop-loss distance shown on your chart
- Click OK and copy the resulting lot size into your order
Using the Script With Prop Firm Accounts
Prop firm rules often cap daily and overall drawdown. You open the terminal, attach the MQL5 risk per trade script, and set risk at 0.5 percent per trade. This keeps every position inside the allowed limits even when volatility spikes.
Combining the Script With Your Existing EAs
Many traders run EAs that already manage entries. You still need to control risk. Run the script on the same symbol first, note the lot size, then load the EA with that fixed lot or let the EA read the value if it supports external inputs. The seller page at https://www.mql5.com/en/users/fjuniverse/seller lists several EAs that accept external lot-size values.
Common Input Mistakes to Avoid
- Entering stop-loss in points instead of pips on five-digit brokers
- Forgetting to update the risk percentage after a large deposit or withdrawal
- Using the script on a different symbol than the one you intend to trade
- Skipping the verification step that shows the final lot size before order placement
Testing the Script on a Demo Account
Load the script on a demo chart, enter 1 percent risk and a 30-pip stop, and watch the lot size appear. Place a manual trade with that size and confirm the potential loss matches your risk amount. Repeat the test with different stop distances until the numbers feel consistent.
Trading involves risk of loss. Past performance does not guarantee future results.
Frequently Asked Questions
Can I use the script on any broker?
Yes, the calculation works on any MT5 broker as long as you enter the correct pip value for that symbol.
Does the script place trades automatically?
No, it only calculates the lot size. You still place the order yourself or let your EA handle execution.
How often should I run the script?
Run it once before each new setup or whenever your account balance changes significantly.
Can I share the script with other users?
Check the license that came with the file. Most risk scripts are for personal use only.
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