.ex4 vs .ex5 — which one do you need?
.ex4 runs only in MetaTrader 4; .ex5 runs only in MetaTrader 5. They are compiled programs for two different platforms, so pick the file that matches the terminal your broker gave you. Everything on this site is tagged MT4 or MT5 so you can filter to the right one.
What the extensions mean
| .ex4 | .ex5 | |
|---|---|---|
| Platform | MetaTrader 4 | MetaTrader 5 |
| Language it was compiled from | MQL4 | MQL5 |
| Install folder | MQL4/Experts or MQL4/Indicators | MQL5/Experts or MQL5/Indicators |
| Runs on the other terminal? | No | No |
| Source-code equivalent | .mq4 | .mq5 |
How to tell which terminal you have
- The window title says MetaTrader 4 or MetaTrader 5 (often with the broker's name in front).
- Help → About shows the version and build number — MT4 builds are in the 1300s–1400s, MT5 builds are 3000+ / 4000+.
- Your data folder contains an MQL4 folder (MT4) or an MQL5 folder (MT5).
- Only MT5 has the Market Depth window and netting/hedging account types.
Other files you'll meet
- .mq4 / .mq5 — source code. Open in MetaEditor (F4 from the terminal) and press Compile (F7) to produce the .ex4/.ex5. Most files here are already compiled.
- .set — a preset of input values. Load it from the EA dialog → Inputs → Load. A .set for MT4 doesn't load in MT5 unless the input names match.
- .zip / .rar — archives; extract first, then install the .ex4/.ex5 inside.
Which should you use?
Whichever your broker account runs on. Many brokers offer both; if you can choose, MT5 is the newer platform (more timeframes, better tester, hedging or netting accounts) and most new EAs are released as .ex5 first — but plenty of well-known robots exist only as .ex4. Browse both here: free MT4 EAs · free MT5 EAs.
Next: how to install the file.
Frequently asked questions
Is .ex5 better than .ex4?
Neither is "better" — they target different terminals. .ex5 runs on the newer MT5 platform; .ex4 runs on MT4. Use the one that matches your broker account.
Can I convert an .ex4 file to .ex5?
Not directly. Compiled files cannot be converted; only the source (.mq4) could be rewritten in MQL5 and recompiled by a developer.
Why doesn't my .ex4 show up in MetaTrader 5?
Because MT5 only loads .ex5 files. Download the MT5 version of the EA, or run it on an MT4 terminal.