Trailing drawdown calculator

Every trailing drawdown is three numbers. D is the drawdown distance, fixed in dollars when the account is issued: at Fullport, D = 4% of the starting balance, so $1,000 on a $25,000 account, $2,000 on $50,000 and $5,000 on $125,000. The high-water mark (HWM) is the highest balance the rule has recorded. The floor is the level equity stays above.

• Opening floor = start − D.
• When the reference balance sets a new high: HWM = that balance, and floor = min(start, HWM − D).
• The floor never moves down. Once HWM reaches start + D, the floor equals the start (breakeven) and locks there for the life of the account.
• The account trades normally while equity stays above the floor, compared on every tick.

That is the whole formula, and it is exactly what the engine runs (see the rulebook). The one decision that shapes how a trailing drawdown feels is the *reference balance*: which number is allowed to move the HWM, and when.

An intraday (or real-time) trailing drawdown updates the HWM from live equity, tick by tick, including unrealized profit on open positions. A coin that spikes 40% for ninety seconds drags the floor up with it, and the floor stays there after the candle collapses. An end-of-day (EOD) trailing drawdown updates the HWM once per day, from the closing balance. Fullport uses EOD at 00:00 UTC, and the reference is the realized balance — cash plus the cost basis of anything still open — so unrealized gains never lift the floor at all.

Note what stays the same: under both models the floor is compared with live equity on every tick. EOD only changes when the floor rises, not how often it is tested.

The calculator's defaults are a five-day sequence on a $25,000 account (D = $1,000) where both models apply the identical distance and the identical breakeven lock. The only difference is whether the day's peak or the day's close moves the high-water mark:

Day 2 is the whole story. The trader was up $1,400 intraday, gave most of it back, and closed up $300. Under intraday trailing, that round trip consumed the entire $1,000 cushion: the floor is now at the starting balance while the account sits only $300 above it. Under EOD trailing the round trip cost nothing but the $1,100 of open profit that was never banked.

1. 1

   Set the account and the distance

   Enter the starting balance and the drawdown as a percent of the start. For a Fullport account leave it at 4%; the pricing page lists the three sizes.

2. 2

   Enter day closes

   One realized balance per UTC day, comma-separated. These drive the EOD floor. Your dashboard shows the realized balance; on Fullport an open position counts at its cost, not its marked value.

3. 3

   Optionally enter intraday peaks

   The highest balance each day reached. Leave the field blank to hide the comparison. A peak below the close is treated as the close.

4. 4

   Read the buffer column

   Buffer at close = the close minus the floor that applied during that day. It is the room equity had above the floor that day — the number to plan the next session from.

A trailing drawdown that never stops trailing keeps following you up: a trader up 30% with a 4% trailing floor still has only 4% of room. Capping the floor at the starting balance changes the rule into a static one the moment you are up D. On the $25,000 account, a close at $26,000 or higher locks the floor at $25,000; after that you could run the balance to $29,000 and back to $25,100 with the floor staying at $25,000.

The lock is also why payouts work the way they do. The withdrawal buffer sits at start + D ($26,000 on the $25,000 account), so after a payout returns the balance to the buffer you still have exactly D of room above a locked floor. The payout calculator works that side of the math.

There is no separate daily loss limit on top of the floor — see one floor, no daily drawdown for why one floor suits ordinary memecoin swings better than a daily cap, and daily drawdown vs trailing drawdown for how the two rules differ when a firm runs both.