Drawdown vs loss: the difference that wipes accounts

"I am OK with a 10% drawdown." Almost every retail trader has said it. Almost none of them know what they were agreeing to. Loss and drawdown are different metrics with different consequences, and the distance between the two is where most accounts disappear.

Definitions, precise

• Loss — the negative result of a single trade. Measured per-trade, in account currency or as a percentage of equity at the time of entry.
• Drawdown — the gap between your peak equity ever reached and your current equity. Measured portfolio-wide, in real time, against a running high-water mark.

A trade that loses $100 is a $100 loss. If that loss takes your account from a $10,000 peak to $9,900, it is a 1% drawdown. If you then have four more losing trades and the account drops to $9,500, the drawdown is now 5% — even though each individual loss was 1%. Drawdown compounds. Losses do not.

Open drawdown — the silent killer

There is a second axis: closed vs open drawdown. Closed drawdown is what you see on your equity curve — positions are out, profit and loss is realised. Open drawdown is the unrealised P/L of positions still on. A strategy can look perfectly healthy on closed drawdown while running a 15% unrealised loss across three open positions.

Max drawdown is one number — it is not enough

Every backtest reports maximum drawdown — the deepest peak-to-trough gap across the whole history. It is a useful number. It is also a single point: one bad month decided it, and the other 59 months told a different story. To understand a strategy you need at least three drawdown numbers:

Time under water

A 15% max drawdown that recovers in three weeks and a 15% max drawdown that takes 11 months to recover are not the same risk. The second one is what destroys trader confidence. By month four you start tinkering with the strategy. By month seven you turn it off. By month nine, when the strategy was about to make a new high, you are already on something else.

Time under water is the count of trading days between a peak and the next peak (the "recovery"). A serious backtest shows the distribution: not just the longest, but how long the typical recovery takes. AlphaLab-AI EA reports include this number in every methodology panel.

The psychology trap

Ask a retail trader what drawdown they can tolerate; they will say 20% or 30%. Show them a $30,000 account that is currently sitting at $21,000, and they panic. The number on paper is not the number in your stomach. Halve whatever drawdown you said you could handle — that is your real tolerance.

Drawdown is a property of the strategy — and of you

A trend-following strategy has long drawdowns because it must let winners run through corrections. A mean-reversion strategy has shallow but more frequent drawdowns because it bets against extremes. A scalping strategy has minimal drawdown but blows up suddenly when liquidity vanishes. There is no drawdown-free strategy — only drawdown shapes that fit different temperaments.

The honest version of "what drawdown can I tolerate" is: what shape of drawdown can I tolerate. A long, shallow drawdown that lasts six months feels different from a sharp 8% in a week. Pick the strategy whose drawdown shape your nervous system can handle.

Brokers and prop firms measure differently

Most retail brokers compute drawdown off balance (closed trades only). Prop firms compute off equity (balance plus unrealised). A position that is 6% in the red on an open trade does not count against your "max balance drawdown" on a retail account. It does count, instantly, against a prop firm's trailing drawdown. Same trade, two completely different consequences.

For a deeper look at the prop-firm side, see trailing drawdown vs static drawdown.

The bottom line

Loss is what happens on one trade. Drawdown is what happens to your equity peak. Every losing trade contributes to drawdown; not every drawdown reaches the loss-tolerance you wrote on paper. Build your sizing around the drawdown you can psychologically withstand, not the loss you can intellectually accept. The two are very different numbers.