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Risk management tool

Position size
calculator for stocks & crypto

Know exactly how many shares or coins to buy on every trade. Protect your account by never risking more than you can afford to lose.

DCA calculator Position size calculator Compound interest calculator
$
Total trading capital
% of account 1%
Professional traders risk 1–2% max
$
Price you plan to buy at
$
Price where you exit if wrong
$
Target exit price
$
Per trade (0 for commission-free)
Position size
—
Amount to invest
—
Max loss
—
Potential gain
—
Risk level
Conservative (<1%) Moderate (1–2%) Aggressive (>2%)
Calculation breakdown Value
Risk amount ($) —
Risk per share ($) —
Stop loss distance —
Risk/reward ratio —
% of account used —
Ready to put this into practice?

Open a commission-free trading account and start applying proper position sizing.

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Why position sizing matters

%
Risk a fixed % every trade

Professional traders never risk more than 1–2% of their account on a single trade. This means even a 10-loss streak only costs 10–20% of your capital — recoverable.

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Stop losses define your risk

Your stop loss isn't optional — it's what makes position sizing possible. Without a defined stop, you have no way to calculate how much to buy.

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Consistency beats big bets

Sizing every trade the same way removes emotion from the equation. You're not "feeling" whether to go big or small — the math decides every time.

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Risk/reward is everything

A good trade risks $1 to make $2 or more (2:1 R/R). If your take profit gives you less than 1.5:1, the trade may not be worth taking regardless of how confident you feel.

Frequently asked questions

How is position size calculated?
Position size = (Account size × Risk %) ÷ (Entry price − Stop loss price). For example: $10,000 account, 1% risk, entry at $150, stop at $142.50 → ($100) ÷ ($7.50) = 13 shares.
What percentage should I risk per trade?
Most professional traders risk between 0.5% and 2% per trade. At 1% risk, you can lose 20 trades in a row and still have 82% of your capital. At 5% risk, 20 consecutive losses wipes out 64% of your account.
Does this work for crypto?
Yes — the same formula applies to any asset. The key difference with crypto is that stop losses need to be wider due to higher volatility. A tight stop on Bitcoin will almost always get hit. Factor in typical daily volatility when placing your stop.
What is a good risk/reward ratio?
A minimum of 1.5:1 is generally considered acceptable — meaning you stand to gain $1.50 for every $1 risked. Many traders only take trades with 2:1 or better. A high win rate with poor R/R can still be a losing strategy over time.
Should I always use the full calculated position size?
Not necessarily. The calculator gives you the maximum position size based on your risk parameters. You can always take a smaller position — for example, half size on a less-certain setup. Never exceed the calculated size.

How the position size calculator works

Position sizing answers: how many shares or coins should I buy on this trade? The calculation is driven by three inputs — your account size, the percentage you are willing to risk on a single trade, and the distance between your entry and your stop loss. The formula is: Position size = (Account x Risk%) / (Entry - Stop loss).

Most professional traders risk between 0.5% and 2% of their account per trade. Risking more than 2% means a string of losses can cause severe drawdowns that are difficult to recover from. Risking less than 0.5% often makes the potential reward too small to justify the trade.

How to use this calculator

Learn more in our guide on risk/reward ratios in trading.