Why the source's lot size is the wrong size for you
A 1.00-lot trade means very different things on a $100,000 account and a $2,000 account. On the first it may risk 0.5% of the balance; on the second the same trade could lose a quarter of the account on an ordinary stop. Sizing mode is how a copier turns the source's lot into a lot that makes sense for your account.
The five modes
1. Risk by balance (proportional)
your lots = source lots × (your balance ÷ source balance) × multiplier
Example
- Source balance $10,000 opens 0.50 lots.
- Your balance $2,000, multiplier 1.
- 0.50 × (2,000 ÷ 10,000) = 0.10 lots.
Your trades keep the same proportions as the source: if the source risks 1% per trade, so do you. This is the default and the best choice when you mirror an account whose sizing you trust.
2. Risk by equity
The same formula with equity instead of balance. When either account has open losses, sizes shrink; with open profits, they grow. It reacts faster to drawdowns, which is why it is the usual choice for prop-firm accounts.
3. Lot multiplier
your lots = source lots × multiplier
0.10 × 2 = 0.20. Balances are ignored. Use it when the ratio between accounts is fixed, when currencies differ, or for cent accounts where balance ratios would be misleading.
4. Fixed lot
Every trade opens the same volume, say 0.05, whatever the source used. It's simple, but it throws away the source's own sizing: a high-conviction 2-lot trade and a 0.1-lot hedge become the same size on your side.
5. Risk percent from the stop loss
your lots = (balance × risk %) ÷ (stop distance in pips × pip value per lot)
Example
- Balance $17,000, risk 1% → $170.
- XAUUSD entry 2352.00, stop 2343.50 → 8.50 away; 100 oz per lot → $850 per lot.
- $170 ÷ $850 = 0.20 lots.
This mode ignores the source's lot completely and sizes from the stop, so it needs a stop on every trade. It is the natural choice for Telegram signals and TradingView alerts, which rarely state a size, and it handles different contract sizes between brokers because it reads your broker's own tick value. Try it in the lot size calculator.
Rounding, minimum and maximum lots
Brokers accept volumes only in steps, usually 0.01 lots, sometimes 0.1 or 1.0 on indices and crypto. A careful copier rounds down to the step, so the trade never risks more than calculated: 0.067 becomes 0.06.
- Max lot caps any single trade. It protects you from a source that suddenly sizes up.
- Min lot sets a floor you choose.
- Force minimum lot: when the calculation gives less than the broker's minimum, either open the minimum (more risk than intended) or skip the trade. On small accounts and big-contract symbols, skipping is often wiser.
Different account currencies and cent accounts
Balance and equity ratios compare raw numbers. A source with 10,000 USD and a target with 10,000 EUR look identical, although the euro account is worth more. With a cent account, a balance of 100,000 cents looks like 100,000 dollars. In both cases use a lot multiplier (or fixed lot) and set the ratio yourself, or use risk percent, which works in the target's own currency.
Which mode should you use?
| Situation | Mode | Why |
|---|---|---|
| Mirroring your own or a trusted master account | Risk by balance | Keeps the source's proportions |
| Prop-firm challenge or funded account | Risk by equity + max lot | Shrinks with drawdown |
| Telegram channel or TradingView alerts | Risk percent | Signals carry stops, not sizes |
| Accounts in different currencies, cent accounts | Lot multiplier | Ratios would be misleading |
| Testing a source on demo | Fixed lot (minimum) | Simple to read in history |