14 Aug 2025
“EX4 vs MQ4: What’s the Difference & Why It Matters for Traders”
EX4 vs MQ4: What’s the Difference & Why It Matters for Traders
Meta Description:
Learn the key differences between EX4 and MQ4 files in MetaTrader 4, how they impact trading strategies, and what every forex trader needs to know.
Introduction
If you trade on MetaTrader 4 (MT4), you’ve probably encountered EX4 and MQ4 files when dealing with indicators, scripts, or Expert Advisors (EAs).
While they might seem like two versions of the same thing, they serve completely different purposes — and knowing the difference can save you from legal trouble, technical headaches, and lost trading strategies.
In this guide, we’ll break down EX4 vs MQ4, why it matters, and how each file type affects your trading workflow.
What is an MQ4 File?
An MQ4 file is the source code of an MT4 program.
• Written in the MQL4 programming language.
• Human-readable — you can open it in MetaEditor and see the logic, rules, and formulas.
• Editable — traders and developers can change strategies, adjust risk parameters, or fix bugs.
Example Uses:
• Developing a new custom indicator.
• Editing an EA’s take profit/stop loss logic.
• Debugging a trading script.
What is an EX4 File?
An EX4 file is the compiled version of an MQ4 file.
• Machine-readable — it’s the “locked” executable version of your trading program.
• Created when you compile an MQ4 in MetaEditor.
• Cannot be directly edited — to make changes, you need the MQ4 source code.
Example Uses:
• Distributing your EA or indicator without giving away the source code.
• Running a trading robot on MT4 without risk of code theft.
Why This Matters for Traders
Understanding EX4 vs MQ4 can help you:
1. Protect Your Intellectual Property
If you’ve spent months creating a profitable EA, sharing the EX4 file instead of the MQ4 file prevents others from copying your strategy.
2. Choose the Right File for Collaboration
If you’re working with a developer, they’ll need the MQ4 file to make edits. If you only have the EX4 file, you won’t be able to modify it without decompilation — which is often illegal and technically challenging.
3. Avoid Legal and Ethical Issues
Decompiling EX4 files without permission can violate copyright laws and MetaTrader’s terms of service. Knowing the difference ensures you respect licensing agreements.
4. Save Time in Troubleshooting
If an EA isn’t working as expected, having the MQ4 file makes debugging possible. With only EX4, you can’t see the logic — you can only guess what’s wrong.
Can You Convert EX4 to MQ4?
Technically, it’s possible using decompilation tools, but:
• It’s illegal without the developer’s consent.
• MT4 builds above 600 use stronger encryption, making it much harder.
• Most online “EX4 to MQ4” services are scams or malware traps.
Best Practices for Traders
• Keep Backups: Always save both MQ4 and EX4 versions of your files.
• Distribute Safely: Share only EX4 versions when selling or giving away your tools.
• Work with Trusted Developers: When hiring freelancers, use secure platforms like MQL5.com or Upwork.
• Understand Licensing: Read the terms before using third-party indicators or EAs.
