Ask a professional trader what the single most important number in their method is and the answer is rarely an entry signal. It is the amount they are willing to lose on one trade. For most, that number is around 1% of the account. The rule is old, boring and responsible for more surviving traders than any indicator ever invented.
What the rule says
Before entering a trade, decide where the stop-loss goes. Then choose the position size so that if the stop is hit, the loss is 1% of the account — no more. Everything else about the trade (the instrument, the direction, the target) is free; the size is not.
On a $10,000 account, 1% is $100. If a EUR/USD stop is 25 pips away, the size is $100 ÷ 25 pips = $4 per pip = 0.40 lot. If a gold stop is $20 away, the size is $100 ÷ $20 ÷ $100-per-dollar-per-lot = 0.05 lot. If a Bitcoin stop is $2,000 away, the size is 0.05 coin. The stop distance decides the size, and the risk stays $100 whatever the instrument.
Why 1%
The arithmetic of losing streaks. Even a good strategy — say 55% winners — will produce runs of ten or more consecutive losses over a few hundred trades; that is not bad luck, it is what a coin with a 45% tails probability does. At 1% risk, ten straight losses cost about 9.6% of the account: painful, recoverable, and the strategy is still intact. At 5% risk, the same run costs 40%, and the recovery table says 67% is needed to get back. At 10% risk, the account is down 65% and the trader is probably done.
| Risk per trade | After 5 losses | After 10 losses | Gain needed after 10 |
|---|---|---|---|
| 1% | −4.9% | −9.6% | +10.6% |
| 2% | −9.6% | −18.3% | +22.4% |
| 5% | −22.6% | −40.1% | +67.0% |
| 10% | −41.0% | −65.1% | +187% |
The rule is not about any single trade. It is about making the worst plausible streak survivable, so that the strategy gets to run long enough for its edge to show.
Variations
Some traders use 0.5% for very active strategies (hundreds of trades a month, where streaks are longer in absolute terms) and up to 2% for slow swing strategies with few, high-conviction trades. Beyond 2% is where professionals stop calling it risk management. Whatever the number, the discipline is the same: it is chosen before the trade and it does not move because the setup "looks good".
How copying delivers it
Here is the part that matters most for an IDTraders copier. Proportional copying mirrors the master's trades in proportion to your allocation. If the master risks 1% of their copy-trading account on a trade, your copy risks about 1% of your allocation. You do not calculate the size; the platform does, trade by trade, from the ratio between your allocation and theirs. A well-sized master gives you well-sized trades automatically.
This also means a badly sized master gives you badly sized trades automatically. The rule is inherited, not applied. That makes the one-minute check on a profile — looking at whether the losing trades cluster around a single dollar amount that is a small fraction of the account — the most valuable minute in choosing who to copy.
The one setting that changes it
The Risk Multiplier in the copy form scales every mirrored trade. At 1x you take the master's risk exactly. At 2x a master's 1% becomes your 2%, which the table above says doubles the damage of a losing streak. At 0.5x it becomes 0.5%, which halves it. New copiers sometimes set 2x or 3x because a master's returns look modest; the same setting turns a master's 15% drawdown into a 30% or 45% one, and the recovery arithmetic becomes brutal. Leave the multiplier at 1x until you have seen the master through a losing streak, and if you want more exposure, add allocation rather than leverage.
The rule under stress
The 1% rule is hardest to keep exactly when it matters most: after a losing streak. The temptation is to increase size "to get back faster", which is the moment the arithmetic turns against you; and the second temptation, after a winning streak, is to increase size "because it's working", which converts a run of luck into a larger loss on the first reversal. Masters who keep the rule through both — whose lot sizes in Recent Trades do not grow after wins or losses — are the ones whose drawdown stays a multiple of a single loss rather than a multiple of the account.
Copy-level protection
The master's 1% rule works trade by trade. Your protection at the level of the whole copy is the Auto Stop Drawdown % — the fall in your copy's equity at which the platform closes it. Think of the two together: the master's rule limits how much any one trade can hurt; your auto-stop limits how many hurts you will take before stepping aside. A master at 1% per trade with your auto-stop at 20% means the master would have to lose twenty-odd trades net before the copy stops, which is enough room for any honest strategy and not enough for a broken one.
Risk 1% per trade and no losing streak can end you. Copying inherits the master's sizing, so the whole rule comes down to one check on the profile — and to leaving the multiplier at 1x.
This article is education, not investment advice. Trading and copy trading in leveraged instruments carry a high risk of losing the funds you allocate. Read the Risk Disclosure.