How to Calculate Max Drawdown for Prop Firm Challenges

Maximum drawdown is the total amount your account can lose from its peak before the firm closes your account permanently. It's the most critical number in all of prop trading — more important than the profit target, the split, or the rules. Everything else is secondary to not hitting this limit.

Understanding how to calculate your drawdown floor in real-time — and keep it updated as you trade — is what separates traders who survive long enough to succeed from those who blow accounts through mismanagement.

What Is Max Drawdown

The maximum drawdown is the distance between your highest balance (or starting balance, depending on drawdown type) and the minimum balance you're allowed to reach before account termination. Hit the floor and the account is closed — no warnings, no second chances, no refund.

Example: $100,000 account with 10% max drawdown = your floor is $90,000. If your account balance (or equity, depending on the firm's calculation method) drops to $89,999 — at any point — the account is terminated.

Static vs. Trailing Max Drawdown

Type	Floor Calculation	Does Floor Move?	Example
Static (Fixed)	Starting balance − Max DD %	Never	$100K − 10% = $90K floor always
Trailing	Highest balance − Max DD %	Yes — upward only	Peak $103K − 10% = $92.7K floor

Static drawdown is more forgiving. Your floor never moves — as you build profits, your buffer grows. Trailing drawdown is stricter — as you profit, your floor rises to lock in those gains.

How to Calculate Your Floor

Static Drawdown Formula

Floor = Starting Balance × (1 − Max DD%)
Example: $100,000 × (1 − 0.10) = $90,000

Trailing Drawdown Formula

Floor = Current Peak Balance × (1 − Max DD%)
Example: Peak of $106,000 × (1 − 0.10) = $95,400

After this point: floor = $95,400 (even if balance drops back to $100,000)

Daily Loss Limit Formula (Separate from Max DD)

Daily Floor = Starting Day Balance × (1 − Daily Loss %)
Example: $103,000 starting balance × (1 − 0.05) = $97,850

If balance hits $97,850 that day → account in violation regardless of total drawdown

Real Calculation Examples

Example 1: FTMO $100K Challenge (Static)

• Starting balance: $100,000
• Max drawdown: 10% = $10,000
• Floor: $90,000 (never moves)
• Daily loss limit: 5% = $5,000 from day's starting balance
• You make $5,000 profit → balance $105,000 → floor still $90,000 → buffer = $15,000

Example 2: Apex $100K EOD Trailing

• Starting balance: $100,000
• Max trailing drawdown: $3,000
• Initial floor: $97,000
• After 3 profitable days, account closes at $104,000
• New floor: $104,000 − $3,000 = $101,000
• Buffer remaining: $104,000 − $101,000 = $3,000

Example 3: Trailing Intraday Trap

• Account: $50,000, $2,500 trailing drawdown
• Floor starts: $47,500
• Trade peaks at +$4,000 (intraday) → floor jumps to $51,500
• Trade reverses and closes at +$1,000 → balance $51,000
• Current floor: $51,500 (locked from peak)
• Account is already in breach! Balance $51,000 < floor $51,500

Managing Your Drawdown Buffer

Your drawdown buffer = Current Balance − Current Floor. This is the number you should monitor after every trade, every session, and every day.

Practical buffer management rules:

• At 50% buffer consumed: Reduce position size to 0.5% risk per trade
• At 75% buffer consumed: Reduce to minimum position size; only highest-confidence setups
• At 90% buffer consumed: Stop trading for the day; review your strategy before next session

For a $100,000 account with $10,000 max drawdown (10% static), this means:

Drawdown Used	Action	Trigger
$5,000 (50%)	Halve position size	Balance drops to $95,000
$7,500 (75%)	Minimum size only	Balance drops to $92,500
$9,000 (90%)	Stop trading today	Balance drops to $91,000
$10,000 (100%)	Account terminated	Balance drops to $90,000

FAQ

Is max drawdown calculated from equity or balance?

This is firm-dependent and critically important. Some firms calculate from balance (closed trades only — floating losses don't count). Others use equity (balance + floating P&L — an open trade in loss counts against you immediately). Equity-based drawdown is stricter. Always confirm which method your firm uses.

What happens when you hit max drawdown?

The account is terminated immediately and permanently for that specific funded account. You do not get a warning. You cannot top up the account. You must purchase a new challenge to get funded again.

Can you recover from a large drawdown?

Yes, if you haven't hit the max drawdown floor. Reducing position size and being selective about setups while your buffer rebuilds is the correct approach. The worst response to being near the floor is to take larger trades to "recover faster."