Use points for the stop and the monetary value of one point for one lot. A pip and an MT5 point are not always the same unit. All monetary inputs and outputs use your account currency.
How to use the MT5 lot size calculator
- Enter the account balance and the percentage you want to use for this calculation.
- Measure the stop distance in your symbol's MT5 points.
- Enter the monetary value of one point for one lot, in the account currency.
- Check the estimate against the broker's lot step, minimum volume, margin and stop rules before using it.
Points, pips and tick value: use matching units
One MT5 point is the symbol's quoted point size. A broker tick can have a different size. If the broker supplies a monetary tick value, an approximate monetary value per point is tick value × point size ÷ tick size. Verify the symbol and account currency; the calculator does not fetch live broker data.
For example, assume a USD account, balance 10,000, a calculation at 1%, a stop of 250 points and a point value of 1 USD per lot. The arithmetic is 100 ÷ (250 × 1) = 0.4 lots. These are hypothetical inputs, not a suggested trade or universal broker specification.
On a commonly quoted five-decimal EURUSD symbol, 250 points represents 25 pips. On a hypothetical XAUUSD symbol with point size 0.01, it represents a price distance of 2.50. The monetary value still depends on that broker's contract and account; never copy a forex pip value into the gold calculation.
What the lot estimate excludes
The calculation does not include commissions, spread changes, slippage or gaps. It does not establish available margin or whether the broker will accept a volume. An EA should normalize a computed volume without exceeding the chosen risk budget; if the result is below the minimum lot, it should not silently round up.
For a production MT5 EA, OrderCalcProfit can estimate the result between two prices in account currency. Check the calculation mode and the broker's symbol properties rather than assuming one fixed value works for every instrument.
Why MT5 lot sizing is not identical for every symbol
Forex pairs, gold, indices, crypto CFDs and synthetic symbols can use different contract sizes, tick sizes, tick values and account currencies. A generic calculator cannot safely assume those values. In MT5, check the symbol specification for tick size, tick value, contract size, minimum volume and volume step before using a live order.
XAUUSD position sizing
Gold often behaves differently from major forex pairs because brokers can quote different digits and contract specifications. Rather than hard-coding a universal XAUUSD pip value, use your broker's symbol data. For automated systems, the EA should read symbol properties directly and normalize the requested volume to the broker's minimum, maximum and step constraints.
Risk controls a production EA should enforce
- Maximum percentage risk per trade and across all open positions.
- Broker volume minimum, maximum and step normalization.
- Stop-loss distance validation before sending the order.
- Spread and slippage limits where the strategy requires them.
- Daily loss or equity drawdown protection when specified.
- Clear logging when a trade is rejected or resized.