Skip to content
ENExplore Calculators

Position Sizing Calculator

Work out position sizing instantly with clear inputs, formula shown and shareable results.

About Position Sizing Calculator

Position size should follow from risk, not conviction. Fixing the loss you accept per trade and dividing by the distance to your stop gives the quantity, so a wider stop automatically produces a smaller position.

Formula

Position size

Quantity = (account × risk %) / |entry - stop|

Worked example

With the default values below, Position Sizing Calculator returns Number Of Units To Buy of 400. Change any input above and every figure here is recalculated in your browser.

Inputs used

Account Sizeminimum 0
1,000,000
Risk Per Tradeaccepts 0.05–10 %
1 %
Entry Priceminimum 0
450
Stop-Loss Priceminimum 0
425

Results

Number Of Units To Buy
400
Amount At Risk
$10,000.00
Position Value
$180,000.00
Position As Share Of The Account
18.00%

Step by step

  1. 1Values used
  2. 2Position size
  3. 3Number Of Units To Buy= 400
  4. 4Amount At Risk= 10,000.00
  5. 5Position Value= 180,000.00
  6. 6Position As Share Of The Account= 18.00

Assumptions and limits

  • The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
  • In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
  • Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
  • Figures are estimates for planning only. Market returns are not guaranteed, and rates, limits and tax rules change. This is not financial or tax advice — speak to a qualified adviser before acting.
  • This is an estimate for general information and not professional financial, tax or legal advice. See the full disclaimer for the limits that apply to this kind of calculator.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Figures are estimates for planning only. Market returns are not guaranteed, and rates, limits and tax rules change. This is not financial or tax advice — speak to a qualified adviser before acting.

Frequently Asked Questions

Why cap risk at 1% per trade?

It lets a long losing streak occur without crippling the account — ten consecutive losses cost under 10%.

What if the stop is very close?

The formula produces a large position, so also cap exposure as a share of the account to control gap risk.

Related Calculators

Position Sizing Calculator | Calcrivo