A Forex EA does not trade an abstract EURUSD market. It trades the exact symbol exposed by the connected broker. That symbol may be named EURUSD, EURUSD.a, EURUSDm or something else, and its volume, tick and stop rules can differ from another account.
Symbol names
A Forex EA does not trade an abstract EURUSD market. It trades the exact symbol exposed by the connected broker. That symbol may be named EURUSD, EURUSD.a, EURUSDm or something else, and its volume, tick and stop rules can differ from another account.
A suffix is often harmless when the EA reads the current chart symbol. It becomes a problem when the program searches for a hard-coded name, builds related symbols from text or calculates money risk from assumptions that do not match the broker’s Contract Specification.
A low advertised spread does not prove that symbol naming, volume rules, execution or protective-order distances match the EA.
Contract Specification
| Property | What to inspect | Why it matters |
|---|---|---|
| Symbol name | EURUSD, EURUSD.a, EURUSDm | Whether the EA can find and trade the chart instrument |
| Digits / Point | 4/5 digits or 2/3 on JPY pairs | Pip conversion, distance filters and order prices |
| Contract size | Units represented by one standard lot | Money risk and margin assumptions |
| Tick size / tick value | Minimum price movement and its value | Position sizing and profit calculations |
| Minimum lot / lot step | 0.01, 0.1 or another increment | Whether calculated volume is accepted |
| Stops Level | Minimum distance from market price | Pending orders, Stop Loss and Take Profit validity |
| Trading sessions | When the symbol accepts orders | Session filters and market-closed errors |
Compatibility workflow
Open Market Watch
Right-click the exact symbol and select Specification. Do not rely on values copied from a different account type.
Compare with the EA requirements
Confirm pair, timeframe, quote digits, minimum lot, hedging or netting assumptions, pending-order use and allowed trading hours.
Check the risk calculation
Test the smallest planned lot and compare expected versus displayed margin and tick value. A correct signal with a wrong contract assumption is still unsafe.
Test order distances
On Demo, confirm that pending orders and protective levels are accepted during normal and wider-spread conditions.
Document the environment
Save the broker, server, account type, exact symbol and specification with the EA version and set file.
Common traps
Safe operating rule
The safest installation uses the broker’s actual chart symbol and lets the EA read its properties at runtime. If the program requires a suffix input, enter only the documented suffix, including punctuation and case. Do not rename files or create an offline chart as a shortcut unless the developer specifically requires it.