ARMFMetaTrader 4 and 5: the MT5 lot calculator and margin control
The built-in MT5 lot calculator does not show the main number of risk management: the terminal knows the contract size, the collateral and the pip value, but not how much money you are prepared to lose in this trade. We take apart which values MetaTrader counts precisely and without your involvement, where exactly they sit in the interface and which step stays manual.
MetaTrader 4 and 5 are the terminal a forex account lives in: an order with a stop, collateral for a position, a history of operations and a report. Everything to do with currency arithmetic it counts itself; everything to do with your share of risk stays a manual entry.
What MetaTrader counts without your involvement
The eight values below are recalculated by the terminal itself on every tick. They do not need to be checked with a calculator — you need to know where they sit, because three of them decide whether the position survives to its stop.
| Value | Where in the terminal | How it is obtained |
|---|---|---|
| Balance | the «Trade» tab | the result of closed trades |
| Funds, also known as equity | the «Trade» tab | the balance plus the floating result |
| Margin | the «Trade» tab | the collateral reserved for open positions |
| Free margin | the «Trade» tab | funds minus margin |
| Margin level | the «Trade» tab | funds ÷ margin × 100 % |
| Contract size | the symbol specification | the size of one lot in the base currency |
| Tick value | the symbol specification | price step × contract size |
| Trade result | the «History» tab | the entry and exit prices, the swap, the commission |
The symbol specification opens from «Market Watch» with the right mouse button. That is the first place to look on a new account: it also shows the minimum and maximum size, the size step and the stops level — the minimum distance closer than which the broker will not accept a stop-loss.
A lot calculator for MT4 and MT5: what the terminal does not have
The «New Order» window has a size field and no risk field. The terminal does not ask what percentage of the account you are risking and does not recalculate the size when the stop changes — the trader keeps that link in their head or in a separate tool. The formula the terminal does not apply:
size = money risk ÷ (stop in pips × pip value per lot)
All three factors exist in the terminal. The money risk you set yourself: a share of funds rather than of the balance — with open positions these are different numbers. The stop in pips comes from the chart markup. The pip value per full lot is derived from the specification: for a pair with the dollar in the quote at five-digit prices it is $10 per standard lot.
The contract size, the size step and the minimum stop distance — three numbers without which the calculation will be approximate.
once per pairThe percentage is multiplied by equity rather than by the balance: with open positions the balance overstates the available risk.
before the tradeWith the crosshair on the chart or as the difference between the entry price and the idea invalidation level. Better to round it up than down.
before the tradeThe result is brought to the broker's size step in the smaller direction: rounding up breaks the risk percentage you set.
before the tradeIf the collateral for that size leaves no buffer of free margin, the trade does not pass on risk even when the size formula permits it.
before sendingMargin calculation in MetaTrader: what is reserved for a position
Margin is neither a loss nor a commission but collateral: the broker holds part of the funds while the position is open and returns them at the close. It is counted from the notional rather than from the stop distance, so a position with a tight stop and one with a long stop occupy the same collateral at the same size.
margin = size × contract size ÷ leverage × the rate to the account currency
| Parameter | Value |
|---|---|
| Size | 0.25 lot |
| Contract size | 100,000 EUR |
| Position notional | 25,000 EUR |
| Leverage | 1:100 |
| Collateral in the base currency | 250 EUR |
| The EUR/USD rate | 1.0850 |
| Required margin on a dollar account | $271.25 |
MT5 shows this number right in the order window before sending; in MT4 it has to be calculated or looked up after the fact in the margin line. The difference is significant: in MT5 a mismatch between the size and the deposit is visible before the click.
The margin level in the terminal: from a warning to a forced close
The margin level in the terminal is the percentage ratio of funds to the used collateral, and it is the only indicator that shows in advance how close the account is to a forced close. The thresholds are set by the broker: usually the warning comes at one level while the automatic closing starts at another, lower one.
| Account state | Funds | Margin | Margin level | What happens |
|---|---|---|---|---|
| The position is open | $10,000 | $271 | 3,690 % | an enormous buffer |
| A floating loss of $500 | $9,500 | $271 | 3,506 % | nothing |
| The size raised to 5 lots | $9,500 | $5,425 | 175 % | the buffer is thin |
| A floating loss of $4,000 | $6,000 | $5,425 | 111 % | close to the threshold |
| A floating loss of $5,000 | $5,000 | $5,425 | 92 % | margin call |
| A floating loss of $7,800 | $2,200 | $5,425 | 41 % | stop-out |
The rows of the table differ not in the quality of the forecast but in the size: in the third row the trader increased the position twentyfold, and the safety buffer fell from thousands of percent to a hundred. That is exactly the mechanism by which accounts end without a single error in the analysis.
MT4 or MT5 for risk control
Both versions have lived side by side for many years, and the choice is more often decided by the broker than by preference. For risk management the difference comes down to a few points, and almost all of them favour the fifth version.
Neither version calculates the size for a risk percentage or stops trading after the daily limit. Both tasks are covered by add-ons — advisors and utilities launched inside the terminal.
MetaTrader and risk: short answers
- Where to look up the pip value
- In the symbol specification: the tick value is multiplied by the number of ticks in a pip. For five-digit quotes a pip equals ten ticks.
- Why the size is not counted from the balance
- With open positions the balance does not include the floating loss. The share of risk is taken from funds — the number that reflects the real state of the account.
- What the stops level is
- The minimum distance from the current price closer than which the broker will not accept a stop-loss or a take-profit. It is stated in the specification in pips.
- Does the terminal calculate risk in percent
- No. Neither MT4 nor MT5 has a field for a risk percentage: converting the percentage into lots is done by utilities, calculators or a spreadsheet.
- Is the swap visible before opening a position
- Yes, the swap rates for the long and the short side are stated in the symbol specification. The charge is applied when a position is carried overnight.
- Can the stop be placed together with the order
- Yes, the Stop Loss and Take Profit fields are filled in the order window. A separate step after opening the position is the source of the most expensive things forgotten.
Frequently asked questions
Does MetaTrader have a built-in lot calculator
No. The order window has a size field but no risk field, so converting the percentage into lots stays manual. The task is covered by utilities inside the terminal, a separate calculator or a spreadsheet with the formula.
How the balance differs from funds and which to use for the risk calculation
The balance is the result of closed trades, funds are the balance plus the floating result of open positions. The share of risk is calculated from funds: they show how much money is on the account right now.
Why the required margin is not visible in MT4 before opening a position
The fourth version does not show the collateral in the order window — that is an interface limitation. The margin is calculated in advance by formula or looked up in the status line after opening, which is already too late.
What a margin level of 100 percent means
Funds have become equal to the used collateral: there is no free margin left, new positions cannot be opened, and a further move against the position leads to a forced close at the stop-out level.
How to find out the pip value for a cross pair
Through the symbol specification: the tick value is multiplied by the number of ticks in a pip. On pairs without the dollar in the quote the pip value floats with the conversion rate, so it is checked before the size calculation.
Does the MT5 account type affect risk management
It affects position accounting. Under hedging accounting opposite trades live separately, under netting they add up into one position — the total risk on the instrument is counted differently in these modes.
Can the daily loss be limited by the terminal's own tools
Not as standard. MetaTrader cannot stop trading when a daily loss amount is reached: that function is added by limiter advisors.
What the trade history report shows
The totals: profit, number of trades, profit factor, maximum drawdown and the average trade. It has no dynamics of drawdown by equity and no distribution of results — for that you go to an external service.
Why the size is rounded down rather than by the rules of arithmetic
Rounding up raises the loss at the stop above the set percentage. The difference looks small, but it is systematic: it works in one direction on every trade in a row.
Does the stop have to be placed in the order itself
Technically no, but a stop left in your head does not trigger when the connection drops and does not stop you from changing your mind. The Stop Loss fields are filled in the same window where the size is set.
What to do if the broker does not accept a stop-loss
Check the stops level in the symbol specification: closer than the stated distance an order is rejected. With a tight stop it is sometimes necessary to choose a different entry rather than shorten the distance.
Is there a difference in risk management between a PC and a mobile terminal
The calculations are identical, but advisors and scripts do not run in the mobile version. A mobile terminal is fine for monitoring and closing by hand, while automatic limiters stay on the computer.
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