Decide how much of your account you are willing to lose on a trade before you open it. Then size the position so that hitting your exit costs exactly that amount. Use order types whose failure modes you understand, keep leverage low enough that normal volatility cannot liquidate you, and keep funds you are not actively trading out of reach of a single point of failure. The rest of this guide covers each step, with the numbers behind it.
Why this matters now: 10 October 2025
On Friday 10 October 2025, crypto prices fell sharply after the US President announced an additional 100% tariff on Chinese goods and export controls on software. Coinglass data reported by Bloomberg showed more than $19 billion of leveraged positions liquidated in 24 hours. More than 1.6 million traders were liquidated, and more than $7 billion went in under an hour. Coinglass called it the largest liquidation event in crypto history and said the real total was probably higher, because some venues report liquidations only partially. Days earlier, Bitcoin had set an all-time high above $125,000.
Most of those losses came from leverage, not from the price move itself. A trader holding spot Bitcoin through that day had a painful mark-to-market loss but kept the position. Many traders on high leverage were closed out at the worst point of the move.
The arithmetic of drawdowns
Losses and the gains needed to recover from them are not symmetrical:
| Loss | Gain needed to break even |
|---|---|
| 10% | 11.1% |
| 25% | 33.3% |
| 50% | 100% |
| 75% | 300% |
The required gain is loss ÷ (1 − loss). The deeper the drawdown, the faster the recovery requirement grows. This is the main reason to cap the loss on each trade.
Step 1: Fix the risk per trade
A common rule of thumb is to risk no more than 1–2% of the account on any one trade. This is a convention, not a law. Its value is in the arithmetic: at a fixed 1% of the remaining balance per trade, 10 consecutive losses leave about 90% of the account, and it takes roughly 69 consecutive losses to halve it. That leaves room to find out whether a strategy works before the account is gone.
Retail traders of leveraged products lose money often. When the European Securities and Markets Authority (ESMA) restricted contracts for difference (CFDs) in March 2018, national regulators' analyses showed that 74–89% of retail CFD accounts typically lose money. These figures cover CFDs in the EU, not crypto trading specifically, but the mechanism is the same: leverage applied to volatile prices.
Step 2: Size the position from the stop, not the other way round
Position size (units) = (account balance × risk %) ÷ (entry price − stop price)
Example: a $10,000 account risking 1% ($100), buying at $100,000 with a stop at $97,000:
- Distance to stop: $3,000 per unit
- Position size: $100 ÷ $3,000 = 0.0333 units (about $3,333 of exposure)
With the stop at $95,000, the distance is $5,000 and the position shrinks to 0.02 units. The dollar risk stays at $100. A wider stop means a smaller position, not a bigger loss.
Fitting the stop to volatility
The Average True Range (ATR), introduced by J. Welles Wilder in New Concepts in Technical Trading Systems (1978), measures how far an asset typically moves in a period. It gives no information about direction. Some traders place stops at a multiple of daily ATR so that ordinary noise does not trigger them. The multiple is a judgement call. Wider stops on more volatile assets only work if the position is cut to match, which the formula above does automatically.
Step 3: Know what your stop order actually does
The US Securities and Exchange Commission's investor bulletin on order types describes three orders and how each can fail:
- Stop order: when the stop price is reached, it becomes a market order. The stop price is not a guaranteed execution price. In a fast or thin market, the fill can be far below the stop. On 10 October 2025, this gap was the difference between a planned loss and a much larger one.
- Stop-limit order: when the stop price is reached, it becomes a limit order that fills only at the limit price or better. This removes the gap risk, but the order may never fill if price moves through the limit, leaving the position open.
- Trailing stop: the stop price follows the market at a set percentage or dollar distance as price moves in your favour. Short-term swings can trigger it, and the fill may still be below the trigger.
The SEC also notes that venues may use different prices to decide whether a stop has been hit, for example last trade versus quotes. Check which one your venue uses.
How big should your position be?
Enter your account balance, the share you are willing to lose, your entry price and your stop price to see the position size that keeps the loss at that amount.
| Account balance | Share of the account you accept losing on this trade | Entry price | Stop price (below entry) | Position size |
|---|---|---|---|---|
| 10,000 $ | 1 % | 100,000 $ | 97,000 $ | 0.0333 units |
| 10,000 $ | 1 % | 100,000 $ | 95,000 $ | 0.02 units |
| 10,000 $ | 2 % | 100,000 $ | 97,000 $ | 0.0667 units |
- All four values are your own inputs; the defaults repeat the article's worked example ($10,000 account, 1% risk, entry $100,000, stop $97,000).
- A wider stop gives a smaller position for the same dollar risk; the stop price must be below the entry price for the result to mean anything.
This is arithmetic on your inputs only: it leaves out fees and slippage, cannot promise your stop fills at the stop price in a fast market, and does not check leverage or where the venue's liquidation price sits.
Step 4: Treat leverage as a position-size multiplier
Leverage does not change how much you should be willing to lose. It changes how little margin it takes to reach a given exposure. Size the trade with the Step 2 formula first, then check two things:
- Liquidation price versus stop price. If the venue's liquidation price is closer to entry than your stop, the venue will close you before your plan does. Lower the leverage or the size.
- Notional exposure. At 10x, a 10% adverse move equals the entire margin posted. During 10 October 2025, moves of that size happened within hours.
For comparison, ESMA's 2018 measures capped retail CFD leverage on cryptocurrencies at 2:1. They also required a margin close-out at 50% of the minimum required margin, and negative balance protection per account.
Step 5: Manage the risk-reward ratio
The win rate needed to break even depends on the ratio of average win to average loss: break-even win rate = 1 ÷ (1 + reward/risk). This excludes fees and slippage.
| Risk : reward | Break-even win rate |
|---|---|
| 1:1 | 50% |
| 1:2 | 33% |
| 1:3 | 25% |
| 1:4 | 20% |
A high ratio on paper means little if the targets are rarely reached. Measure your actual average win, average loss and win rate from your trade records.
Step 6: Reduce custody and counterparty risk
Position sizing does not protect you against losing the asset itself. Chainalysis counted more than $3.4 billion stolen in crypto thefts from January to early December 2025. A single compromise of a centralised exchange in February 2025 accounted for about $1.5 billion of that. The FBI attributed it to North Korea, in activity it calls "TraderTraitor". Chainalysis put losses from compromised personal wallets at $713 million in 2025, about 20% of the total.
Practical steps:
- Keep only the funds you are actively trading on a trading venue.
- Store longer-term holdings in a wallet whose keys you control, with the recovery phrase kept offline.
- Use app-based or hardware two-factor authentication rather than SMS, and set up withdrawal address allow-lists where they are offered.
- Before using a venue, check whether it publishes proof of reserves and how it handled past incidents.
Step 7: Put the rules in writing
Tversky and Kahneman's 1992 work on prospect theory estimated that losses weigh about 2.25 times as heavily as equivalent gains. This was a median from a small sample of graduate students, and later meta-analyses put the average somewhat lower, near 2. It helps explain why traders hold losers hoping for a recovery and sell winners early.
Rules decided in advance work against this bias:
- Entry rules: the conditions under which you open a position.
- Exit rules: the stop and the target, set before entry.
- Sizing rules: risk per trade, the maximum leverage, and a maximum total exposure across open positions.
- Stop-trading rules: for example, no new trades after a set daily loss.
- Journal: record the reason, size, outcome and your state of mind for each trade, and review it regularly to find recurring mistakes.
Dollar-cost averaging for long-term holdings
For buying and holding rather than trading, dollar-cost averaging means buying a fixed amount at fixed intervals regardless of price. It reduces the risk of putting everything in at a peak. The trade-off is that money held back stays out of the market, which costs returns in a rising market. It is a way to manage timing risk, not a way to lift returns.
Quick checklist
- Risk per trade fixed before entry (for example 1% of the account)
- Position size calculated from the distance to the stop
- Order type chosen with its failure mode in mind (gap risk or no fill)
- Liquidation price further away than the stop
- Total exposure across correlated positions capped
- Idle funds off the trading venue, with keys you control
- Trade logged in your journal
Limitations: the rule-of-thumb figures here (1–2% risk, ATR multiples) are conventions, not tested guarantees. Nothing in this article is investment advice, and crypto trading can lose all of the capital committed.
