Lot rounding at small balances is secretly your real risk setting
Posted: Sat Oct 31, 2026 8:31 am
On a $200 account, 1 percent risk is $2. With a 6 pip stop on a major, 0.01 lot has a pip value of roughly $0.10, so the stop risks about $0.60 per 0.01 lot. $2 divided by $0.60 is 3.33, which rounds down to 0.03 lot and a real risk of $1.80. Fine.
Now widen the stop to 15 pips. One 0.01 lot costs $1.50 if stopped. Two lots would be $3, which is 1.5 percent. The calculator says 1.33 steps, so the choice is 0.01 (0.75 percent) or 0.02 (1.5 percent). Rounding error is huge in relative terms because the step is large compared with the position.
A few consequences:
- Risk per trade is not a smooth setting. At this size it jumps in steps of about 0.75 percent or more, depending on stop distance.
- Always round down, never to the nearest step. Rounding up on a streak of losers adds up quickly.
- Some brokers offer smaller steps or cent accounts. Check whether the commission per lot gets a minimum charge that makes tiny tickets disproportionately expensive.
- Trade with stop distances that land close to a whole step rather than forcing the size.
Do the maths on the last twenty trades and compare the intended risk with the actual dollar risk after rounding. The gap is usually larger than expected.
How far off was your actual risk from the number you thought you were using?
Now widen the stop to 15 pips. One 0.01 lot costs $1.50 if stopped. Two lots would be $3, which is 1.5 percent. The calculator says 1.33 steps, so the choice is 0.01 (0.75 percent) or 0.02 (1.5 percent). Rounding error is huge in relative terms because the step is large compared with the position.
A few consequences:
- Risk per trade is not a smooth setting. At this size it jumps in steps of about 0.75 percent or more, depending on stop distance.
- Always round down, never to the nearest step. Rounding up on a streak of losers adds up quickly.
- Some brokers offer smaller steps or cent accounts. Check whether the commission per lot gets a minimum charge that makes tiny tickets disproportionately expensive.
- Trade with stop distances that land close to a whole step rather than forcing the size.
Do the maths on the last twenty trades and compare the intended risk with the actual dollar risk after rounding. The gap is usually larger than expected.
How far off was your actual risk from the number you thought you were using?