Crypto Position Size Calculator

Size a trade so a stop-loss costs only what you risk. Free, private, and calculated entirely in your browser.

Position Size Calculator

Work out how much to buy so a stop-loss only costs you the amount you decided to risk, and check the reward-to-risk ratio.

Risk amount

$100

Position size

0.033333

Position value

$2,000

Reward : risk

3 : 1

To risk 1% ($100) of a $10,000 account, buy 0.033333 units (about $2,000). Your stop is 5% away from entry, so if it hits you lose exactly your planned $100. At your target the reward-to-risk ratio is 3 to 1, a healthy setup.

How this is calculated

units = (account x risk%) / |entry - stop|; reward-to-risk = |target - entry| / |entry - stop|

  • Sizes the position so a stop-out equals your chosen risk amount exactly.
  • Ignores trading fees, funding, and slippage, which slightly increase real losses.
  • A target price is optional; leave it blank to size on risk alone.