Crypto Position Size Calculator
This free crypto position size calculator tells you exactly how much to buy so that a losing trade only costs a set fraction of your account. Enter your account size, the percentage you are willing to risk on the trade, your entry price, and your stop-loss price, and it works out your position in coins and dollars. Everything runs in your browser, so nothing you type is saved or sent anywhere.
How to Use the Position Size Calculator
The calculator needs four numbers. Enter your account size in US dollars, the percentage you are willing to risk on this single trade (many traders use 1%), your planned entry price per coin, and your stop-loss price, the level at which you will exit if the trade goes against you. The results update as you type, and you can press Calculate or the Enter key at any time.
You do not need to work out any quantities yourself. From your account size and risk percentage the calculator finds how many dollars you are putting at risk, and from the gap between your entry and stop it finds how many coins that buys. It also shows the total dollar value of the position and what share of your account that represents.
The Formula Behind It
The math is simple arithmetic you can check by hand:
- Amount at risk = account size × risk %
- Risk per coin = |entry price − stop-loss price|
- Position size (coins) = amount at risk / risk per coin
- Position value = position size (coins) × entry price
The absolute value in the risk-per-coin step just means the distance between your entry and your stop, regardless of which is higher. Whether you are going long with a stop below your entry or planning a short with a stop above it, only the gap matters.
A Worked Example
Say you have a $10,000 account and you decide to risk 1% on a trade, which is $100. You plan to buy at an entry price of $30,000 and set your stop-loss at $28,000. Your risk per coin is the gap between them, $2,000. Divide your $100 of risk by that $2,000 and you get a position size of 0.05 coins. At the $30,000 entry price, those 0.05 coins are worth $1,500, or 15% of your account. If the price falls to your stop, you lose exactly the $100 you planned to, no matter how large the position looks in dollar terms.
Why Position Sizing Matters
Position sizing is what separates surviving a losing streak from blowing up your account. Everyone has losing trades; the traders who last are the ones who make sure no single loss can do real damage. The widely used 1-2% rule caps your loss on any one trade at 1-2% of your account, which means even a run of ten losses in a row costs only a small fraction of your capital and leaves you plenty of room to recover. To go deeper on this idea, read our full guide to crypto position sizing and how it fits into crypto risk management.
One thing to watch: if the calculated position value comes out larger than your whole account, it means the only way to take that trade at that risk level would be to use leverage, which is risky and can lead to losses greater than your deposit. If that happens, widen your stop, lower your risk percentage, or simply take a smaller position instead.
Common Mistakes to Avoid
- Trading with no stop-loss. Without a stop there is no defined risk per coin, so there is no way to size a position responsibly. Decide where you are wrong before you enter.
- Risking too much per trade. Risking 10% or 20% of your account on one idea means a short losing streak can cripple you. Keep it to 1-2%.
- Moving the stop to avoid a loss. Widening your stop after you are already in the trade breaks the whole plan and turns a small planned loss into a large one.
- Confusing position value with risk. A $1,500 position is not a $1,500 risk. Your risk is only the distance to your stop, which is why sizing math matters.
Practice Before You Trade for Real
Knowing your position size is only half the picture. Knowing whether you can actually hold to your stop without moving it is the other half. With CustomCrypto, you can practice sizing and managing trades across 38 cryptocurrencies at real market prices using virtual money, so you can build the habit before any real capital is on the line, all without risking a cent.
Frequently Asked Questions
How do I calculate position size in crypto?
Start by deciding how much of your account you are willing to lose on the trade, for example 1% of a $10,000 account, which is $100. That is your amount at risk. Next, find your risk per coin by taking the absolute difference between your entry price and your stop-loss price. Divide the amount at risk by the risk per coin to get your position size in coins. Multiply that by the entry price to see the dollar value of the position.
What is the 1% risk rule?
The 1% risk rule says you should never risk more than 1% of your total account on a single trade. On a $10,000 account that caps your loss at $100 per trade. Many traders use a 1-2% range. The point is that no single losing trade can meaningfully damage your account, so a normal losing streak cannot wipe you out and you stay in the game long enough to learn.
Why does position size depend on my stop-loss?
Your stop-loss defines how far the price can move against you before you exit, which is your risk per coin. A tight stop close to your entry means a small loss per coin, so you can buy more coins for the same dollar risk. A wide stop means a larger loss per coin, so you must buy fewer coins to keep the same amount at risk. Position size and stop distance move in opposite directions to hold your total risk constant.
Is my data saved or sent anywhere?
No. This calculator runs entirely in your browser using JavaScript. Nothing you type is saved or sent to any server. When you close the tab, the numbers are gone. That matches CustomCrypto's privacy-first approach: your data stays on your device.
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