Held, not spent

The number worth calculating is the one that gets locked (South Africa)

Sizing tools are usually approached as a way to picture a result. Read from the money side they answer something plainer and far more immediate: if this position opens, how much of the balance stops being available, and how much is left beside it?

Opening a position moves part of the balance into used margin — your own money, on the same account, locked while the position lives and released when it closes. A sizing calculation tells you that amount in advance, in the account's own currency. The order ticket states the same thing before you confirm, which makes the ticket the final authority and the calculator a way of arriving already knowing the answer.

What the sum tells you and what it does not

Question	Does the sum answer it?
How much becomes locked as margin	Yes — that is its whole job
How much stays free for anything else	Yes, by subtraction from free margin
What one step of price is worth to you	Yes, converted into the account currency
Whether the trade is a good idea	No. Nothing in the arithmetic has an opinion

Three arithmetic answers and one that no calculator anywhere produces. Watching the split happen live

Compare the answer against free margin, not the balance

This is the one habit that changes what the sum is for. The balance is the settled total, and part of it may already be held against positions that are open right now. The pot a new position draws on is free margin.

So the useful comparison is: the amount this trade would lock, against the amount currently free. Doing it the other way — measuring against the balance — is how a position that looked comfortable turns out to leave almost nothing available, and it is a purely clerical mistake rather than a trading one.

The same logic applies to money leaving. A withdrawal draws on free margin too, which is why a request can come back smaller than the balance suggests while nothing at all is wrong. Which pot each word counts

Reading the result in three steps

What you see: an amount, expressed in the account's own currency — not in the units the instrument is quoted in.
What to read next: the free-margin figure on the account. The gap between the two is what would still be available afterwards.
The next step: open the order ticket for the same size and compare. The ticket is what actually applies, and any disagreement means a field was filled in differently.

An independent guide: it holds no balance and executes nothing. The figure that applies is the one shown on your own order ticket, inside your Exness account area.

What the sum leaves out entirely

Two costs live outside it and both are stated elsewhere on the screen. The spread — the gap between the buying and selling price at that moment — is paid at entry, which is why a fresh position often shows a small negative figure straight away. The swap is charged for carrying a position past the daily rollover, and the ticket states it before the trade is confirmed.

And one boundary sits under everything: clients never lose more than they've deposited, so the account cannot travel past zero. Losing the amount deposited stays possible, and no sum on this page changes that.

Questions about the figure on the screen

Is the margin figure a fee?

No. It is your own money held while the position is open, and it returns to free margin when it closes.

Which currency is the answer in?

The account's own, whatever the instrument is quoted in.

Why does the ticket disagree with my sum?

Usually a different size or instrument was entered. The ticket is the version that applies.

Should I compare against balance or free margin?

Free margin. The balance may already include amounts held against open positions.

Does a bigger size lock more?

Yes, and it also makes each step of price worth more to you. Both effects arrive together.

Does the sum include the spread?

No. The spread is built into the two prices and paid at entry, separately from margin.

Can I run this on a practice account?

Yes — the same tickets and the same margin lines appear there, with virtual money behind them.

Does the arithmetic say whether to take the trade?

No. It answers how much would be locked, and nothing at all about whether locking it is wise.

Get the sum wrong where nothing gets locked.

A practice account shows the same ticket and the same margin lines with virtual funds behind them. The button goes through a partner link to the official exness.com website.

Open a free demo at Exness