How do I size a trade from the risk instead of guessing?

Trade › the order ticket › Risk-based sizing (auto)

Switch on Risk-based sizing (auto). Enter the share of the account you accept losing in Risk per trade and the Stop distance; the ticket computes the Position size so that a stopped trade loses exactly that amount. Use size copies it into the order. The block also shows the money at risk, the reward at target, and the break-even win rate.

Step by step

  1. Switch on Risk-based sizing (auto)In the order ticket, under the size row.
  2. Risk per tradeA percentage of the account. The ticket shows it in money too.
  3. Stop distanceHow far the stop sits from the entry, as a percentage. Farther stop, smaller size.
  4. Reward : RiskPick a preset or type your own. Reward if target hit updates with it.
  5. Use sizeCopies the computed size into the ticket. On perps, Margin at N× and the liquidation distance appear next to it.

Good to know

  • Breakeven win rate is the share of trades that must win for this Reward : Risk to come out flat. Your win rate and Expected value below it come from your own journal history, not from a guess.
  • The app never picks the percentage for you. The guide on how much to risk explains how to choose one.
Try it in BuildTrade™

Trade › the order ticket › Risk-based sizing (auto). The free plan needs no card.

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Updated October 2026 · Trading · Not what you needed? Tell support and the article gets fixed.