Crypto position size calculator

The single most-skipped step in retail trading is the math that comes between "I want to take this trade" and "what size do I click." Without it, position size becomes whatever the chart looks like in the moment — usually too big when the trader feels confident, too small when they don't. Both fail differently. Both fail.

The math is two lines. Decide a fixed percentage of your account you're willing to lose if the stop hits — typically 1-2%, no more. Divide that dollar amount by the stop distance per coin, and you have the position size that turns "stop hit" into "exactly the loss I planned." This calculator runs those two lines for you so the answer is in front of you before you click. Once you have a size, see what break-even R:R you need at your win rate — sizing alone doesn't make you profitable; the reward-to-risk math has to clear the hurdle too.

Why size matters more than entry timing

Most retail traders obsess over entry — what level, what indicator, what time of day. The math says position size has a larger effect on long-run results than entry quality does. A trader with average entries and consistent 1% risk-per-trade will outperform a trader with elite entries and inconsistent sizing over any reasonable sample. Sizing is the part of trading you control completely; entry quality is partially a function of luck.

The structural reason: small wins from a good entry don't compound if a single oversized loss erases them. Conversely, a trader sizing properly can absorb several bad entries without breaking the equity curve. Run a back-test of any working strategy with random ±20% size noise applied to each trade and the equity curve degrades meaningfully. Run the same back-test with random ±20% entry-price noise and the curve is roughly unchanged. The math is unforgiving in one direction and forgiving in the other.

What 1-2% actually means

The convention of risking 1-2% of your account per trade isn't conservative — it's the level at which a normal losing streak doesn't end the run. At 2% risk, a 10-loss streak (about 0.1% probable at a 50% win rate, much rarer at 70%) reduces the account by roughly 18%. Painful, recoverable. At 5%, the same streak removes 40%. At 10%, it removes 65% — the kind of drawdown that requires a 200% gain to undo.

This is also why the "scaling up risk to make up for slow progress" instinct is so dangerous. Doubling your risk-per-trade does not double expected return; it doubles the size of each loss while leaving the win rate unchanged. The expected outcome moves linearly with risk; the variance of outcomes grows quadratically. You feel more, you make about the same, and the worst outcomes get dramatically worse.

For the broader picture of how sizing interacts with strategy edge, the risk-of-ruin and Kelly criterion calculators cover the math of when a strategy survives at all. For the deeper read on stop placement specifically — the geometric trade-off between win rate and reward-to-risk that drives every sizing decision — see the post on where to put the stop loss.

How to use this for an actual trade

The workflow most retail traders should run before clicking buy:

1. Decide the stop loss first, based on chart structure or your strategy's invalidation rule. Don't pick a price-distance because it makes the size convenient.
2. Confirm the risk percentage you've committed to. 1-2% is the floor for most strategies; deviating up needs a specific reason, not a gut feeling.
3. Enter all four numbers above. The position size is what you click. The dollar notional tells you whether you can afford spot-only or need leverage.
4. Place the trade with a hard stop on the exchange, at the price you typed in. The reason mental stops fail is documented elsewhere; the calculator's whole job is to make hard-stops the cheap default.

If the calculator outputs leverage above 10x, the strategy is asking for more position than the account can comfortably support. If under 1x, you're spot-only on this trade — fine, but be aware the win-leverage from any leverage at all is also lost. There's no right answer; the calculator just shows you which regime you're in.

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