Position size calculator: shares from account risk & stop distance

Position sizing starts with how much you can afford to be wrong. Enter your account value, the percentage you are willing to risk, and your entry and stop prices to see the maximum number of shares.

Formula

Maximum shares = Account risk budget ÷ Risk per share.

What you need

Account value
Maximum risk percentage
Entry or current price
Stop price

Worked example

With a $20,000 account and 1% risk, your budget is $200. Buying at $50 with a stop at $46 risks $4 per share, so the maximum is 50 shares: a $2,500 position, 12.5% of the account.

Risk first, shares second

Most investors choose a share count and then hope the stop is acceptable. Reversing the order, fixing the maximum loss first, keeps any single position from doing outsized damage, however volatile it is.

Why wide stops mean smaller positions

A volatile stock needs a wider stop to avoid being shaken out, and a wider stop means more risk per share. For the same risk budget, that translates into fewer shares. Sizing from the stop is how volatility-aware stops and sensible position sizes fit together.

Watch the position weight too

A very tight stop can produce a position that is a large share of the account. Even if the stop limits the expected loss, a gap through the stop can cost more, so check the position weight as well as the risk figure.

Common questions

How much of my account should I risk per trade?

Many investors risk between 0.5% and 2% of their account on a single position. The right figure depends on your goals and tolerance; the calculator shows the position size for whatever limit you choose.

Does position sizing work with any stop method?

Yes. Any stop, whether fixed, ATR-based or structural, gives a risk per share, and the position size follows from your risk budget.

Portfolio Analytics

Portfolio Analytics gives investors a clearer view of diversification, hidden exposure, and concentration risk across stocks, ETFs, sectors, regions, currencies, and account scopes.

Explore Portfolio Analytics