BTC
ETH
SOL
BNB
XRP
ADA
DOGE
LINK
AVAX
DOT
MATIC
LTC
Strategy backtester Super
Run EMA, RSI, breakout, MACD and pullback rules over up to 1,000 real candles, with fees, slippage and an ATR stop.
Strategy builder Super
Write your rules as a one-page document: markets, regime, setup, trigger, stop, target, risk and review.
Replay trainer
Practise on real past markets one candle at a time. A month of trades in an evening, scored in R.
Position size
The single most important calculation in trading. Risk and stop distance decide size. Never the other way round.
size = (equity x risk%) / |entry - stop|Trade planner
The whole plan on one card: what you risk, what you stand to make, and the win rate this trade needs to be worth taking. Fees included.
break-even win rate = 1 / (1 + reward:risk)R multiple and expectancy
Expectancy is what one average trade returns. A strategy that loses 6 times out of 10 can still be strongly profitable.
E = (win% x avgWin) - (loss% x avgLoss)Kelly fraction
The bet size that grows an account fastest, if your win rate and payoff were known exactly. They never are, which is why nobody sane trades full Kelly.
f* = win% - (loss% / payoff)Risk of ruin simulator
The same strategy, run 500 times with the luck reshuffled. Every line below has the same win rate and the same payoff. The spread between them is variance, and the worst lines are what your risk per trade has to survive.
Leverage and liquidation
Check that the liquidation price sits well beyond your stop. If it does not, the exchange is managing your risk instead of you.
liquidation move ≈ (1 / leverage) - maintenance marginProfit, loss and fees
What the trade actually returns once both legs of the commission are paid.
Funding cost on a perpetual
Funding is paid on the whole position, not on your margin, every eight hours. A rate that looks tiny becomes a real cost when the position is leveraged and held for days.
funding = notional x rate x 3 x daysReading these three together
- Leverage does not change how far price must move to hit your stop. It changes how much margin that stop costs.
- Pick the stop from the chart, the size from the stop, and only then the leverage that fits that size into your margin.
- Liquidation should sit at least twice as far away as your stop. If it does not, lower the leverage.
- With positive funding, longs pay shorts. With negative funding, shorts pay longs.
- Fees are paid on the notional too. A 0.1% fee on a 10x position is 1% of your margin per side.
Compounding and drawdown
Two truths at once: steady returns compound quickly, and drawdowns need more to recover than they took away.
Averaging and break-even
What a second entry does to your average price, and what the position then needs to get back to level.
Averaging down into a broken thesis is the most expensive habit in retail trading. Adding to a position is only defensible when it was planned before entry.
What a loss costs to win back
gain needed = loss / (1 - loss)| You lose | $1,000 becomes | Gain needed to be level | What that means |
|---|---|---|---|
| -5% | $950 | +5.3% | A normal bad week. Shrug. |
| -10% | $900 | +11.1% | Still routine at 1% risk per trade. |
| -20% | $800 | +25.0% | Time to cut size and review the journal. |
| -30% | $700 | +42.9% | Most traders change the method here, usually at the worst moment. |
| -50% | $500 | +100% | You must double the account just to be back. |
| -75% | $250 | +300% | The account has to quadruple. |
| -90% | $100 | +900% | A tenfold gain. In practice, the account is gone. |