Risk Per Trade: The 1% Rule and Sizing From Your Stop
Why Risk Per Trade Matters
Every trade you take should risk a small, known slice of your account. Not because losses are bad — they're a normal part of trading — but because the size of a loss determines how hard you have to work to recover from it. Lose 10% and you need an 11% gain to break even. Lose 50% and you need a 100% gain. This math gets ugly fast, which is why controlling risk per trade is one of the few things you fully control before you ever click buy.
The 1% Rule
A common guideline is to risk no more than 1% of your total account on any single trade. "Risk" here doesn't mean the amount you spend on the position — it means the amount you'd actually lose if your stop-loss gets hit.
This distinction matters. You can put $2,000 into a trade and still only be risking $50 of that, if your stop is close to your entry. Position size and risk amount are two different numbers, and the 1% rule is about the second one.
Computing Size From Stop Distance
The formula is straightforward:
Position Size = (Account Size × Risk %) ÷ Stop Distance %
Here's how it works with a concrete example.
Say you have a $5,000 account and you're following the 1% rule. That means you're willing to risk $50 on this trade.
You're looking at SOL, currently trading at $150. Based on recent support, you decide your stop-loss will sit at $141 — a stop distance of $9, or 6% below entry.
Now solve for position size:
$50 (risk) ÷ 6% (stop distance) = $833 position size
So you'd buy roughly $833 worth of SOL (about 5.5 SOL at $150). If the price drops to your stop at $141, you sell, and your loss is close to $50 — 1% of your account. If SOL runs instead, your upside isn't capped by this calculation at all; only your downside is defined in advance.
Notice what happens if you tighten the stop. If you'd set your stop at $147 (a 2% stop distance) instead of $141, your position size would jump to $2,500 — more than double your original size, because a tighter stop lets you risk the same dollar amount on a bigger position. Stop distance and position size move in opposite directions for the same risk amount.
Common Mistake
The most frequent error is deciding position size first — "I'll put $1,000 into this" — and only figuring out the stop-loss afterward. This backwards approach means your actual dollar risk is whatever happens to fall out of the math, not something you chose. Two trades with the same $1,000 position size can carry wildly different risk if one has a 3% stop and the other has a 15% stop. Always start from your risk percentage and stop distance, then let the position size be the output — not the input.
On MAPLUStrade
You can practice this without any real money at stake using MAPLUStrade's paper trading tool. Set up a simulated USDC account, then run a long-term plan where each entry is sized using the 1% rule from this lesson — pick your stop distance first, calculate the size, and place the trade. The portfolio page will track your drawdown automatically as trades play out, so you can see directly how consistent 1% sizing keeps your equity curve smoother compared to sizing trades on gut feel. It's a low-stakes way to build the habit before applying it live.
Recap
Risk per trade should be a fixed, small percentage of your account — not whatever amount happens to fit your position. Set your stop distance first, then calculate position size from your risk percentage, so every trade's downside is known before you enter it.
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*This lesson is educational content only and not financial advice. Trading involves risk of loss, including loss of principal, and past performance does not guarantee future results.*