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LEVEL 4 · Building a Market-Study Workflow · LESSON 17

Position Sizing / Risk Calculator

Estimate a maximum contract quantity from a risk budget, stop distance, and tick value.

Written lesson
A study log only, not a skill check.

LEARNING OBJECTIVE

Estimate a rounded-down quantity from a risk budget, stop distance, and Tick Value.

IN ONE SENTENCE

Position sizing starts with a risk amount set in advance, then estimates quantity from the price risk for one contract. The result is an educational estimate, not a cap on actual losses.

Basic concepts

TickExplain

The smallest permitted price increment for a contract.

Tick valueExplain

The monetary change for one contract when its price moves by one Tick.

Risk per contractExplain

An estimate found by multiplying stop distance in Ticks by the contract's Tick value.

Software walkthrough

Menu placement may vary by platform version. Use the current official guide when a label differs.

  1. 01

    Step 01

    Enter account size and planned risk percentage to calculate Max Risk.

    Check: Confirm the displayed settings match the selected inputs.

  2. 02

    Step 02

    Enter stop distance and instrument to see the estimated dollar risk per contract.

    Check: Confirm the displayed settings match the selected inputs.

  3. 03

    Step 03

    Divide Max Risk by the per-contract estimate, round down to a whole contract, and review the resulting planned risk.

    Check: Confirm the displayed settings match the selected inputs.

Concept diagram

Concept illustration for education; it contains no live or historical market data.

Study scenario

Assume $10,000×0.5%=$50; if unit risk is $20, quantity is two. Arithmetic only.

Slippage, gaps, volatility, and execution can change the actual result. The estimate does not guarantee a maximum loss.

Common mistakes

  • Issue: Treating risk percentage as return.

    Check the input, version, session, data, or setting that controls this behavior.

  • Issue: Ignoring slippage and execution.

    Check the input, version, session, data, or setting that controls this behavior.

Lesson summary

  1. 01

    Budget comes first.

  2. 02

    Round quantity down.

  3. 03

    The output is an estimate.

PRACTICE EXERCISE

Calculate two hypothetical inputs and compare stop-distance effects.

Use static, historical, or browser-local sample data only.

OFFICIAL REFERENCES

Checked against public documentation

Source review: 2026-10-09

This lesson paraphrases official material. Check the installed version for current interface details.

Education note

Software and market education only. No direction signals, live order instructions, or performance claims.

Trademark and independence

NinjaTrader® is a registered trademark of NinjaTrader Group, LLC. No NinjaTrader company has any affiliation with the owner, developer, or provider of the products or services described herein, or any interest, ownership or otherwise, in any such product or service, or endorses, recommends or approves any such product or service.