Crypto position size calculator

By the Blockhorizon Editorial Team · Updated 2 October 2026 · How we check facts

How is position size calculated?

Position sizing turns a loss you decide in advance into a trade size. The calculator uses these steps (percentages as decimals, so 1% = 0.01):

1. Money at risk = account balance × risk %
2. Distance to stop = entry price − stop-loss price (ignoring the minus sign)
3. Fees per coin = fee % × (entry price + stop-loss price) — one fee to open, one to close at the stop
4. Loss per coin at stop = distance to stop + fees per coin
5. Position size (coins) = money at risk ÷ loss per coin at stop
6. Position value = position size × entry price

If the stop is below the entry price, the calculator treats the trade as a buy. If the stop is above it, it treats the trade as a short (betting on a fall). The arithmetic is the same either way.

What does a worked example look like?

Using the calculator’s default numbers — a $10,000 balance, 1% risk, entry at $50,000, stop-loss at $47,500 and a 0.1% fee on each side:

Two things change the answer a lot. Widen the stop to $45,000 (10% below entry) and the size halves to about 0.0196 coins, worth about $981.35, for the same $100 at risk. Raise the risk to 2% with the original stop and the size doubles to about 0.0770 coins, worth about $3,849.86.

Computed examples for illustration only; these prices are not a prediction.

Who decides the risk percentage?

You do. We found no regulator rule that sets a maximum percentage of your account to risk on a single trade, and this calculator does not recommend one. The 1% in the box is only a starting number so the example works. Pick a figure based on how much money you could lose without harm to your finances, then test it.

A small percentage still adds up when losses come in a row. Risking 2% of the current balance on each of 10 losing trades turns $10,000 into about $8,170.73, a fall of 18.3%. At 5% per trade, the same streak leaves about $5,987.37, a fall of 40.1%.

How do you use the calculator?

1. Enter your balance — the money in the account you trade from, not your total savings.
2. Enter the risk % you have chosen for this trade.
3. Enter the price you expect to buy at and the price where you would exit if you are wrong.
4. Enter the trading fee from your platform’s fee schedule.
5. Press Calculate. If the position value is larger than your balance, the trade would need borrowed money (leverage), and the calculator warns you.

To see what fees and spreads cost on a full round trip, use the crypto fee calculator. To test a planned trade from buy to sell, use the crypto profit calculator.

Why can you lose more than the calculator shows?

The result assumes your stop-loss fills exactly at the stop price. It may not. The US Securities and Exchange Commission (SEC) explains that a stop order, “also referred to as a stop-loss order”, is triggered when the price reaches the stop price, and warns: “The stop price is not the guaranteed execution price for a stop order.” In a fast market the order can fill well below your stop, so the real loss is larger. Read more in market, limit and stop orders.

The Australian Securities and Investments Commission (ASIC) notes on its Moneysmart site: “Stop loss orders can limit your losses, but you may also pay a premium price to guarantee your stop loss order.” Only that kind of guaranteed stop fixes the exit price, and it costs extra.

The calculator also leaves out the spread, network or withdrawal fees and taxes. And the UK Financial Conduct Authority (FCA) says that if you invest in crypto you should be prepared to lose all your money. Position sizing limits a planned loss; it does not make crypto safe. Before using any platform, read the red flags of crypto scams.