Position Sizing and Stop-Loss in Crypto: How Much to Buy

Most beginners spend their time hunting for the perfect entry and almost no time on the two decisions that actually decide whether they survive: how much to buy and where to get out. This guide gives you a one-formula method for position sizing, a way to place a stop-loss where it means something, and the arithmetic behind why small losses keep you in the game. It builds on the exit rules in our swing trading guide and the levels covered in the support and resistance guide.

You can run every number below yourself in the position size calculator. Type in your account, the risk you accept, your entry and your stop, and it returns the position size.

This is educational content, not financial advice. Nothing here predicts where any coin will go.

Why size matters more than entry

Two traders take the same trade with the same stop. One buys with 5% of their account, the other with 80%. The first shrugs off a stop-out. The second has lost a large share of their capital on one idea and needs a much bigger gain to get back to even.

Entry timing is a coin flip you can only nudge. Size is the part you fully control: before you click buy, you can choose exactly how much a loss will cost.

The one-formula method

Position sizing by risk comes down to two steps.

1. Decide how much money you are willing to lose if the stop is hit. Account size multiplied by your risk percentage gives you this number.
2. Divide that money by the distance between your entry and your stop. The result is the number of units (coins) to buy.

In one line: units = (account x risk %) / (entry - stop). For a short, use the distance from entry up to the stop.

Worked example 1: a normal stop

• Account: $10,000
• Risk per trade: 1%, so money at risk = $10,000 x 0.01 = $100
• Entry: $100
• Stop: $95
• Distance to stop: $100 - $95 = $5 per unit
• Units: $100 / $5 = 20 units
• Position value: 20 x $100 = $2,000, which is 20% of the account

If the stop is hit at $95, you lose 20 x $5 = $100, which is exactly 1% of the account. The position is 20% of your account, but the loss is 1%. That gap between position size and risk is the whole point.

Worked example 2: a wider stop gives a smaller position

Same account, same 1% risk, same $100 entry, but the chart says the stop belongs at $90.

• Distance to stop: $100 - $90 = $10 per unit
• Units: $100 / $10 = 10 units
• Position value: 10 x $100 = $1,000, or 10% of the account

Doubling the stop distance halves the position, while the money at risk stays $100. A wider stop is not "riskier" when you size correctly. You just buy less.

Why a tight stop gives a bigger position, and why that is a trap

The formula has a side effect that catches many people. The closer your stop is to your entry, the larger the position the formula allows. Keep the same $10,000 account, 1% risk and $100 entry, and shrink the stop:

Stop	Distance	Units	Position value	Share of account
$90	$10	10	$1,000	10%
$95	$5	20	$2,000	20%
$98	$2	50	$5,000	50%
$99	$1	100	$10,000	100%

A $1 stop on a $100 coin lets you put the entire account into one position while "only risking 1%". The math is correct, and the trade is still a bad idea. A stop 1% from entry sits inside the normal back-and-forth of a daily candle on most coins, so ordinary movement stops you out. Fills are not guaranteed at your price, so a gap of a few dollars on 100 units costs far more than planned. And fees, spread and a bad fill all scale with the notional size.

The fix is to let the chart set the stop first, then let the formula give the size. If that size feels too large, the stop is probably too tight for the coin: reduce the position or skip the trade.

Choosing your risk percentage

Many traders risk somewhere between 0.5% and 2% of the account per trade. That is common practice, not a rule, and nothing makes one number correct for everybody. The right figure depends on how many trades you take and how much of a drawdown you can sit through without breaking your own rules.

What the percentage really controls is how a losing streak feels. Here is what ten consecutive losses leave behind, assuming each loss is exactly the risked percentage of the remaining account:

Risk per trade	Account left after 10 straight losses	Drawdown
1%	0.99^10 = 90.4%	about 9.6%
2%	0.98^10 = 81.7%	about 18.3%
5%	0.95^10 = 59.9%	about 40.1%
10%	0.90^10 = 34.9%	about 65.1%

At 1%, ten losses in a row leave about $9,040 on a $10,000 account: annoyed, not finished. At 10% per trade, the same streak leaves about $3,490. Streaks happen to every method, so the useful question is what you want to be left with when one arrives.

Choose your risk before the trade, not after it starts to hurt. If you catch yourself raising it to "make it back", lower it instead.

Drawdowns compound against you

Losses and gains are not symmetric. If you lose 10%, you do not need a 10% gain to recover. You need more:

Loss	Gain needed to get back to even
-10%	+11.1%
-20%	+25%
-30%	+42.9%
-50%	+100%
-75%	+300%
-90%	+900%

The formula is gain needed = loss / (1 - loss). A 20% loss leaves 80 of your original 100, and getting from 80 back to 100 means growing the remainder by 20/80 = 25%. A 50% loss leaves 50, and you must double it.

This is why small, controlled losses beat large ones. The deeper the hole, the steeper the climb and the more tempting bigger risks become. Position sizing keeps you in the shallow part of that table.

Where to place a stop-loss

A stop has one job: mark the price at which your reason for the trade is wrong. Everything else about it follows from that.

Put it below structure

For a long, the natural places are below a recent swing low, below a support level, or below a moving average the price is bouncing from. If price closes clearly through that level, the idea has failed, and you want out. Our support and resistance guide explains how to find those levels, and the moving averages guide covers the averages.

Here is Solana's price with the 50-day and 200-day moving averages. To use it for stop placement, look for the points where the price line turned back up after a dip: those turning points are swing lows. A stop for a long entered near one of them goes a little below that low, or below the moving average that held it. The distance from your entry down to that stop is the number you feed into the sizing formula.

Avoid round numbers and arbitrary percentages

• Exactly on a round number. A stop at $100.00 or $50,000 sits where a great many other people put theirs. Orders cluster there, and price often wicks through the level and then returns. Place the stop a small buffer beyond the level instead.
• A fixed percentage for every coin. "I always use 5%" ignores that a large, steady coin and a small, jumpy coin move very differently in a day. The stop should come from the chart, with the percentage as an outcome rather than an input.

A note on ATR

One way to account for how much a coin normally moves is the average true range (ATR), which measures the typical daily range. Some traders place the stop a multiple of the ATR away from entry so that ordinary noise does not hit it. Our ATR guide covers it in detail. CoinSeekly does not calculate ATR for you, so you would read it from your charting tool.

Stop types and why stops do not always fill at your price

A stop-market order becomes a market order once price touches your stop. It is almost certain to execute, but at whatever price is available. A stop-limit order becomes a limit order at the price you set. It protects you from a bad fill, but if price jumps past the limit, your order may never execute and you stay in the position while it keeps falling.

Suppose you hold 20 units with a stop-market at $95 for a planned loss of $100. A sharp move blows through $95 and the order fills at $93. Your loss is 20 x $7 = $140, not $100. With a stop-limit at $94.50, the same move may skip your order entirely, and you are still holding 20 units at $93, now under water by $140 with no exit in place.

That gap is called slippage. It is usually small on liquid coins in calm markets and can be large on thin coins or during news-driven spikes. Crypto trades around the clock, so your stop can be hit while you sleep, often when order books are thin.

The honest summary: a stop limits your intended loss, it does not guarantee it. Allow for that by sticking to liquid coins and keeping positions small enough that one bad fill is survivable. If you trade with leverage, the situation is worse, because the exchange can close you out before your stop is reached. See the leverage and liquidation guide and the liquidation calculator.

Reward-to-risk and the win rate you need

A stop tells you how much you can lose. The reward-to-risk ratio tells you how much you stand to gain relative to that. If your stop is $5 below entry and your target is $10 above, the ratio is 2:1.

The ratio sets the win rate you need to break even before fees: breakeven win rate = 1 / (1 + reward-to-risk).

Reward-to-risk	Breakeven win rate	Meaning
1:1	50%	win one in two
1.5:1	40%	win two in five
2:1	33.3%	win one in three
3:1	25%	win one in four

Check the 2:1 row with $100 at risk: three trades, one winner paying $200 and two losers costing $100 each, nets $0.

Two cautions. First, this is arithmetic, not evidence: it tells you what you would need, not what any method delivers. A target needs a reason such as a prior resistance level, not just a wish for a higher ratio. Second, a stop pushed very close to entry to make the ratio look better runs into the noise problem above. The crypto profit calculator is a quick way to check what a target and stop mean in money.

Trailing stops

A trailing stop moves in your favour as the trade works, locking in some gain while leaving the position open. A simple manual version for a long:

• Enter at $100 with the stop at $95. Your risk per unit is $5.
• Price rises to $110. Move the stop up to $100, break-even. The trade can no longer lose, apart from fees and slippage.
• Price makes a higher low and rises to $120. Move the stop to just below the new swing low, say $110.

Never move a stop away from price to give it "more room"; stops only move with the trade. Trail too tightly and normal pullbacks stop you out, too loosely and you give back much of the gain. The swing trading guide shows how partial profits and trailing fit into a full trade plan.

Position limits and correlation

Sizing each trade correctly protects you from one bad trade. It does not protect you from five trades going wrong at once, and in crypto that happens because coins tend to move together. When the broad market sells off, most coins fall at the same time, and the smaller ones often fall further.

Hold five coins and risk 1% on each, and you may feel diversified. In a market-wide drop all five stops can trigger within hours, and you lose about 5%, not 1%. Five correlated positions often behave like one large position.

Ways to handle this: set a ceiling on total open risk across all trades, treat similar coins as partly the same bet, and cap the share of your account in any single coin. Stops hit during a market-wide move are also more likely to slip.

Fees count too

Every trade pays fees in and out. Suppose your exchange charges 0.1% per side (a placeholder, so check your own rate). On the $2,000 position from example 1, that is about $2 to enter and just under $2 to exit, so your real loss at the stop is closer to $104 than $100. On very tight stops the effect is bigger: at the $98 stop in the earlier table, the $5,000 position pays about $10 in fees on $100 of risk, a tenth of your budget. If you want precision, build an allowance for fees into the risk amount before dividing.

How to use position sizing with CoinSeekly

CoinSeekly gives you the starting list, you supply the judgment.

1. Find coins that are close to support. A close, structure-based stop means a better reward-to-risk and a more sensible position size. The near-support list ranks coins by their distance to the nearest support, and the screener lets you filter by that distance yourself.
2. Understand what the support level is. In the product, support is a mechanical swing pivot: a day whose low is the lowest of the three days on either side, over the last year of daily candles. It is a reasonable first marker, not a verdict, so check the level by eye on the chart.
3. Place the stop below that level with a buffer, not on it.
4. Enter the numbers in the position size calculator for the units and the share of the account.
5. Check the leverage trap if you trade with margin, using the liquidation calculator. The product does not detect ATR, so volatility-based stops are a job for your own charting tool.

The bottom line

Decide how much you can lose, find the stop on the chart, and let the formula tell you how much to buy: account x risk % divided by the entry-to-stop distance. A wider stop means a smaller position, and a tight stop that allows a giant position is a trap, not a bargain. Keep per-trade risk modest, because losses compound against you (a 50% drawdown needs a 100% gain), and remember that stops can slip and that correlated coins can all stop out together.

Next steps: run your own numbers in the position size calculator, browse the near-support list for setups with a close stop, and read the swing trading guide to see sizing inside a complete trade plan. If you use leverage, the leverage and liquidation guide is the essential follow-up.