Understand how fixed size, proportional equity and proportional balance settings affect your copied trades, and why your results can differ from the trader you follow.
The master is the trader you copy. The copier is your account. Balance excludes profit or loss on open trades; equity includes it.
These simplified examples assume both accounts use the same currency and equivalent instrument contract specifications. Profit-and-loss comparisons assume matching entry and exit prices and exclude fees, spread differences and slippage. Actual copied trades also depend on minimum lot size, lot increments, available margin and your copy settings. GOLD is used only as an illustration.
1. Fixed size: why a profitable master can mean a losing copier
Master starting equity: $10,000. Copier starting equity: $500. Fixed size: 0.01 lot.
With fixed sizing, each copied trade uses your selected lot size, even when the master changes theirs.
| Trade | Master position | Master P&L | Copier position | Copier P&L |
|---|---|---|---|---|
| 1: loss | 0.10 lot | −$100 | 0.01 lot | −$10 |
| 2: profit | 1.00 lot | +$200 | 0.01 lot | +$2 |
| Net result | +$100 | −$8 |
On the losing trade, your position was 10% of the master's size: 0.01 ÷ 0.10. On the winning trade, it was only 1%: 0.01 ÷ 1.00.
You therefore copied a larger share of the loss than of the profit. Fixed size does not preserve the master's relative position sizing, so a profitable sequence for the master can still produce a loss for you.
2. Proportional equity at 100%: the effect of rounding up
Master equity when sizing the trade: $10,000. Copier equity: $500. Copy proportion: 100%. Minimum size for this example: 0.01 lot, with Round Up to Minimum Lot enabled.
The proportional calculation is:
Copied lots = master lots × (copier equity ÷ master equity) × copy proportion
If the master opens 0.10 lot:
0.10 × ($500 ÷ $10,000) × 100% = 0.005 lot
Rounding this up to 0.01 lot doubles the calculated position size. For that position, an equivalent price move produces approximately twice the percentage gain or loss relative to your starting equity.
For example, a $100 loss on the master's 0.10-lot trade is 1% of their starting equity. A $10 loss on your rounded 0.01-lot trade is 2% of yours.
How this can amplify drawdown
In a simplified basket where every copied position is twice its intended proportional size, a loss equal to 50% of the master's starting equity would correspond to approximately 100% of the copier's starting equity, before any forced closures or other differences.
This is an illustration, not a prediction of when your account will stop out. Equity ratios can change as positions are opened, and rounding can affect each position differently. Margin requirements, leverage, other positions and the broker's stop-out rules determine when forced closures occur; that may happen before equity reaches zero.
Key point: selecting 100% proportional equity does not ensure matching percentage exposure when minimum-size rounding increases your positions. This is especially important for smaller accounts.
3. Proportional equity at 10%: what the percentage means
Master equity: $10,000. Copier equity: $500. Copy proportion: 10%.
If the master opens 0.50 lot:
0.50 × ($500 ÷ $10,000) × 10% = 0.0025 lot
Another way to understand this is that the calculation uses $50 of effective copying equity: $500 × 10%. That is 0.5% of the master's $10,000 equity, so the calculated copied size is 0.5% of 0.50 lot.
At 100%, the same calculation would instead produce:
0.50 × ($500 ÷ $10,000) × 100% = 0.025 lot
These are calculated sizes before minimum-size and lot-increment handling. If the instrument's minimum is 0.01 lot, 0.0025 lot is below that minimum. Whether it is skipped or increased depends on the applicable settings and rules. If rounded up to 0.01 lot, the position is four times the calculated 0.0025-lot size.
Key point: 10% does not mean copying 10% of the master's lot size, and it is not a 10% maximum-loss limit. It scales your equity-based sizing calculation.
4. Proportional balance at 100%: balance is not equity
Master balance: $10,000. Copier balance: $500. Copy proportion: 100%.
The balance ratio is $500 ÷ $10,000 = 5%.
Copied lots = master lots × (copier balance ÷ master balance) × copy proportion
Master opens 1.00 lot → calculated copier size is 0.05 lot.
Master opens 0.50 lot → calculated copier size is 0.025 lot.
The actual size of the second trade depends on permitted lot increments and rounding rules. For example, if the instrument uses 0.01-lot increments and the applicable rule rounds down, 0.025 becomes 0.02 lot. Do not assume this rounding rule applies to every account or instrument.
If closed trades reduce the copier's balance to $400 while the master's remains $10,000, the ratio becomes 4%. A new 1.00-lot master trade then calculates to 0.04 lot. Deposits and withdrawals can also change the balance ratio.
Why floating losses matter
Now consider these accounts:
| Master | Copier | |
|---|---|---|
| Balance | $10,000 | $500 |
| Equity | $8,000 | $250 |
The balance ratio remains 5%, so a new 1.00-lot master trade still calculates to 0.05 lot for the copier. However, the copier now has only $250 of equity remaining.
For comparison, a 100% equity-based calculation at that moment would produce 1.00 × ($250 ÷ $8,000) = 0.03125 lot, before rounding.
Balance-based copying does not adjust for floating profit or loss. In this example, it therefore produces a larger new position relative to the copier's remaining equity than equity-based copying would. Insufficient margin may prevent a trade from opening, and continuing losses may lead to margin call or stop-out.
Before you start copying
Check which sizing method you selected and what the percentage controls.
Check the instrument's minimum size, lot increments and your rounding setting.
Remember that fixed sizing and rounding can make your returns differ substantially from the master's.
Review your available margin and CopyMate drawdown controls. No sizing method guarantees a profit or prevents losses.