A stop loss turns an open-ended loss into a fixed number you choose before the trade. It is what makes position sizing possible and removes the worst decision in trading: when to cut a loser while you are in it. Here is how to place one that actually works.
The Definition
A stop loss is the one decision a trade should never make for you in the moment.
A stop loss is a pre-set order, placed at a defined price, that closes a losing trade the moment price reaches that level. It caps the loss at a number you chose in advance, before any emotion was attached to the position.
That single act does three things. It defines the risk on the trade. It makes correct position sizing possible, because risk per trade is the distance to the stop multiplied by the size. And it removes the in-the-moment decision of when to give up, the decision a losing position is least equipped to make well.
Without a stop, a single trade carries an undefined loss. No risk-reward ratio can be calculated, and one bad position can do damage that no winning streak repairs. The stop is what converts an open-ended risk into a known, controlled one.
Why It Is Non-Negotiable
Every other risk decision depends on the stop already being set. It is the first number, not the last.
Your loss is the distance from entry to stop times your position size. Without a stop there is no defined risk, just a position with an open downside.
Position size is calculated backwards from the stop. Decide the risk, find the stop, then a position size calculator gives the size that fits.
Choosing when to cut a loser while holding it is the worst decision in trading. The stop makes it once, calmly, before the trade is on.
The stop sets the risk leg, so a risk-reward ratio only exists once it is placed. No stop, no honest expectancy.
Markets gap and trends extend. A stop bounds the loss on any single trade so one position cannot decide the fate of the account.
Consistent, defined losses keep drawdown shallow and recoverable. Undefined losses are how shallow dips become deep holes.
The Four Types
Every method answers one question: at what price is the trade idea wrong? They just measure that distance differently.
| Type | How It Works | Best For |
|---|---|---|
| Fixed price | A set price or pip distance from entry, decided in advance | Simple, rule-based systems and fast execution |
| Percentage | A fixed percent of the entry price, scaling with the instrument | Longer-term positions and varied-price assets |
| Volatility (ATR) | A multiple of Average True Range, so it widens in fast markets | Avoiding stop-outs from normal noise |
| Structure-based | Just beyond a swing high or low, the level that proves the idea wrong | Trading with the chart rather than a number |
Where To Place It
The stop belongs where the trade is proven wrong, then the size is set so that distance equals your risk. Never the reverse.
The most common mistake is placing the stop at a dollar amount you can stomach, then hoping price respects it. That is backwards. The market does not know or care what you can afford to lose.
Place the stop where the trade idea is invalidated: beyond the swing low for a long, beyond the swing high for a short, past the level that says the setup has failed. Then use a position size calculator to choose a size where that distance equals one unit of risk. The stop comes from the chart, the size adapts to the stop.
Avoid the obvious round numbers and the exact swing point itself. Stops cluster there, and price is often drawn to clear them before reversing. Give the level a small buffer so normal noise does not take you out of a trade that was still valid. For the full framework, see trading risk management.
The Mistakes
A stop loss only protects the account if it is real, placed well, and left alone.
Trading with an undefined loss. One position can then do damage that months of disciplined trades cannot undo.
A stop you intend to honour but never place. The exact moment it should trigger is the moment you are least likely to act on it.
Sliding it further away to avoid the loss. This converts a planned, small loss into an unplanned, large one almost every time.
Placed inside normal price noise to feel safe. It gets clipped repeatedly on trades that were actually still valid.
Picking a position size first, then adding a stop wherever it lands. Risk per trade becomes whatever happens, not what you chose.
Resting it on an obvious price or the exact swing point, where stops pile up and price is often pulled in to clear them first.
The Real Problem
A trade closed at three times its planned risk still books as one loss. Without the data, the broken discipline is invisible.
Trading without a real stop
You see the loss, not the breach.
Tracker Fx
Planned versus realised, made visible.
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A stop loss is a pre-set order that closes a trade once price reaches a defined level, capping the loss at a point you chose in advance. It turns an open-ended risk into a fixed, known number before the trade is even placed.
A stop loss defines the risk on a trade, which is what makes correct position sizing possible. It also removes the in-the-moment decision of when to cut a loss, the decision a losing position is least equipped to make well. Without one, a single trade can do damage no winning streak repairs. See trading risk management for the wider framework.
Place it at the price that proves the trade idea wrong, the invalidation level, not at a dollar amount you can stomach. Use structure such as a swing high or low, then use a position size calculator so the distance to that level equals your intended risk. Avoid obvious round numbers where stops cluster.
A stop loss becomes a market order when the stop price is hit, so it fills at the next available price and prioritises getting out. A stop limit becomes a limit order at a set price, so it will not fill worse than that price but can be skipped entirely if price gaps through. A stop loss favours certainty of exit, a stop limit favours price control.
Yes. Tracker Fx includes a 14-day free trial with full access to all journaling and analytics features. The free trial is available for all platforms except MetaTrader, which requires a paid plan.
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