Max Drawdown: Setting a Personal Loss Limit

Max drawdown measures the largest peak-to-trough fall in an account. Learn how to calculate it, turn it into a personal loss limit and set rules in advance.

What is max drawdown?

A drawdown is a fall from a previous high. Max drawdown is the largest such fall over a period: the percentage decline from a running peak to the lowest point reached before that peak is exceeded again.

Drawdown (%) = (current value − running peak) ÷ running peak

The idea is formal enough that US commodity regulations define a “worst peak-to-valley drawdown” for commodity pool and trading-advisor disclosures: the greatest cumulative percentage decline in month-end net asset value during a period in which the starting value is not regained. You can apply the same yardstick to your own account.

Worked example: finding the max drawdown in an account

Suppose a hypothetical account records these month-end values:

The max drawdown is −25%, from March’s $12,500 peak to June’s $9,375 trough. Getting back to $12,500 took a 33.33% gain from the trough, and the account spent five month-ends below its peak, April through August.

Notice that in June the account was still only 6.25% below its January starting value, yet it was 25% below its peak. A drawdown is measured from the peak, not from what you put in; measuring from your deposit hides the gains you gave back.

Warning: Deposits and withdrawals distort drawdowns. If you had added $2,000 in May, the balance would read $12,000, just 4% below the peak, while the investments themselves were down 20%. Use returns that strip out cash flows, as explained in time-weighted vs money-weighted returns.

Why set a loss limit before you need it

Risk tolerance is your ability and willingness to lose some or all of an investment in exchange for potentially higher returns. Both parts are easier to judge calmly than in the middle of a fall, when a limit invented on the spot tends to be either abandoned or set by fear. The SEC’s guidance for day traders makes the same point from another angle: risk only money you can afford to lose, and never money you need for living expenses or retirement.

The math argues for deciding early as well. Losses need larger percentage gains to recover: 20% needs 25%, 25% needs 33.33%, and 50% needs 100%, so each extra point of drawdown is harder to undo than the last. Drawdown recovery math and percentage gains vs losses cover this asymmetry in detail.

Turning a drawdown limit into rules

Step 1: Pick the limit and what it applies to

Choose the largest drawdown you would accept on a defined pot of money, such as a trading account or your crypto holdings, rather than on your whole net worth. Suppose it is 20%.

Step 2: Check what the limit implies for risk per trade

If you risk a fixed fraction r of the account per trade, the number of consecutive losses that breaches a limit D is n = ln(1 − D) ÷ ln(1 − r), rounded up. Starting from a $10,000 peak:

If five losses in a row would end the plan, the risk per trade is too large for the limit. The 1% risk rule explains how a risk per trade becomes a position size.

Step 3: Write tiered responses

A single cliff-edge limit invites denial. Tiers give you earlier, smaller actions:

In this example plan, drawdowns up to 10% are business as usual. Between 10% and 15%, the risk per trade is halved. Between 15% and 20%, no new positions are opened while you review. At 20%, the limit is reached, and you stop to reassess before doing anything else.

Step 4: For holdings without stops, size by stress loss

If you hold crypto for the long term without stops, a loss limit becomes an allocation limit. Divide the loss you could tolerate by a severe but plausible drop. With a $50,000 portfolio, a $6,000 tolerable loss and a hypothetical 75% stress drop, the most you would hold in crypto is $6,000 ÷ 0.75 = $8,000, or 16% of the portfolio. The stress figure is a planning assumption, not a forecast.

Applying the rules to the example

In the example account, April’s −12% drawdown triggers the second tier and halves the risk per trade. May’s −20% reaches the limit; if open positions are closed and no new ones are opened, the account stops falling at about $10,000 instead of reaching $9,375.

The rules have a cost too. While you pause, you may miss part of the rebound to $12,900. A loss limit trades some upside for a floor under the damage, and that trade-off is exactly what you decide in advance.

Know its limits as well: a loss limit is a trigger, not a guarantee. If the account sits at −17% and a single crash takes it to −26%, the 20% limit is breached by six points before you can act. Positions that move together make such jumps more likely, as crypto correlation explains, and stops can fill well below their price, as covered in stop-loss placement.

Common drawdown-limit mistakes

• Measuring from your deposit instead of the peak. It ignores gains you have already given back.
• Moving the limit once it is hit. A limit you can renegotiate at −20% is only a suggestion.
• Letting deposits hide losses. New money can make a 20% drawdown look like 4%.
• Raising risk to recover faster. It shortens the road to the next, deeper drawdown.
• Setting a limit you can’t act on, such as one that assumes you will be watching the screen during a weekend crash.

Our ROI and CAGR calculator shows the gain needed to recover from any loss, so you can see the cost of a drawdown before it happens.

The bottom line

Max drawdown measures the deepest fall from a peak, and each point of it is harder to recover than the last. Choose a limit while you are calm, check what it implies for risk per trade, and write tiered actions for the way down. A limit won’t stop every gap, but it turns a painful decision into one you have already made.

This content is for education only and is not financial, investment, tax or legal advice. Crypto assets are volatile and you can lose money. Examples use hypothetical numbers. See our disclaimer and editorial policy.