Even after a successful decompilation, your work is not done. The generated MQ4 rarely compiles without errors. Here is what to expect and how to fix it:
Many free indicators/EA developers will share the MQ4 if you ask politely. For paid products, offer to purchase the source code (often an extra fee).
The honest answer is: It depends on your risk tolerance and technical skill.
If you are a hobbyist trying to learn from a free, unprotected indicator, using a free decompiler on an offline computer is a reasonable approach. You will get something workable after some manual cleanup.
If you are a professional managing client funds or relying on a commercial EA, free decompilation is too risky. The hidden bugs, malware threats, and legal liabilities outweigh the cost savings. Instead, either pay for a reputable decompilation service or (better yet) rewrite the strategy from scratch based on its observed behavior. How To Convert Ex4 To Mq4 Free
Final recommendation for most traders: Do not rely on decompilation. Use it only as a last resort to recover your own lost code. For everything else, request the source code from the developer or choose open-source EAs/indicators from GitHub.
If the EX4 file was compiled without excluding debug information, some older versions of MT4 might allow limited recovery:
This method is largely obsolete and works only on extremely old EX4 files (pre-Build 600).
If free tools are so problematic, what about paid decompilers? Companies like "Ex4 to Mq4 Converter" (available on various coding forums) charge $200-$500. Even after a successful decompilation, your work is not done
| Feature | Free Tool | Paid Tool (e.g., Decompiler X) | |---------|-----------|-------------------------------| | Cost | $0 | $200-$500 | | Success Rate | 40-60% | 85-95% | | Code Readability | Obscured (var_1, var_2) | Half-readable (attempts to restore names) | | Support | None | Email/forum support | | Malware Risk | High | Medium (still a gray market) | | Build Updates | Never | Occasional |
Verdict: If you are decompiling a $30 EA for personal learning, a free tool is fine. If you are trying to recover a lost proprietary strategy worth thousands, pay for a professional service or rewrite from scratch.
Short answer: Yes, but with significant caveats.
Free conversion tools exist. They are called decompilers. A decompiler attempts to reverse the compilation process, turning bytecode back into something resembling MQ4 code. If the EX4 file was compiled without excluding
However, there is no perfect free decompiler. The results are almost never identical to the original source code. Variable names are lost, comments are gone, and the structure is often obfuscated.
After testing multiple free solutions, one tool consistently gets mentioned in trading forums: "EX4 to MQ4 Decompiler v4.0.4" (released by a group known as "LazyTrader" or similar variants).
Pros:
Cons:
Realistic success rate: For simple indicators (under 500 lines), ~80%. For complex EAs with multiple include files and libraries, ~40%.